diff --git a/packages/vue-i18n-core/src/composer.ts b/packages/vue-i18n-core/src/composer.ts
index 5bebc0c7d..efe914ece 100644
--- a/packages/vue-i18n-core/src/composer.ts
+++ b/packages/vue-i18n-core/src/composer.ts
@@ -13,8 +13,7 @@ import {
   assign,
   inBrowser,
   deepCopy,
-  hasOwn,
-  warnOnce
+  hasOwn
 } from '@intlify/shared'
 import {
   isTranslateFallbackWarn,
@@ -611,24 +610,6 @@ export interface ComposerOptions<
    * @defaultValue `undefined`
    */
   messageCompiler?: MessageCompiler
-  /**
-   * @remarks
-   * An option to make `te` behavior specification before v9.6
-   *
-   * @VueI18nTip
-   * :new: v9.10+
-   *
-   * @VueI18nWarning
-   * This flag will be removed in v10.
-   *
-   * @VueI18nSee [GitHub Issue](https://github.com/intlify/vue-i18n-next/issues/1738)
-   *
-   * @VueI18nSee [`te`](composition#te-key-locale)
-   *
-   * @defaultValue `false`
-   *
-   */
-  translateExistCompatible?: boolean
 }
 
 /**
@@ -1954,17 +1935,6 @@ export function createComposer(options: any = {}): any {
   const flatJson = options.flatJson
   const _ref = inBrowser ? ref : shallowRef
 
-  const translateExistCompatible = !!options.translateExistCompatible
-  if (__DEV__) {
-    if (translateExistCompatible && !__TEST__) {
-      warnOnce(
-        getWarnMessage(
-          I18nWarnCodes.NOTICE_DROP_TRANSLATE_EXIST_COMPATIBLE_FLAG
-        )
-      )
-    }
-  }
-
   let _inheritLocale = isBoolean(options.inheritLocale)
     ? options.inheritLocale
     : true
@@ -2414,11 +2384,11 @@ export function createComposer(options: any = {}): any {
         const targetLocale = isString(locale) ? locale : _locale.value
         const message = getLocaleMessage(targetLocale)
         const resolved = _context.messageResolver(message, key)
-        return !translateExistCompatible
-          ? isMessageAST(resolved) ||
-              isMessageFunction(resolved) ||
-              isString(resolved)
-          : resolved != null
+        return (
+          isMessageAST(resolved) ||
+          isMessageFunction(resolved) ||
+          isString(resolved)
+        )
       },
       () => [key],
       'translate exists',
diff --git a/packages/vue-i18n-core/src/legacy.ts b/packages/vue-i18n-core/src/legacy.ts
index 4fe4f6f88..670071129 100644
--- a/packages/vue-i18n-core/src/legacy.ts
+++ b/packages/vue-i18n-core/src/legacy.ts
@@ -1487,8 +1487,6 @@ function convertComposerOptions<
   const datetimeFormats = options.datetimeFormats
   const numberFormats = options.numberFormats
   const flatJson = options.flatJson
-  const translateExistCompatible = (options as unknown as ComposerOptions)
-    .translateExistCompatible
 
   return {
     locale,
@@ -1509,7 +1507,6 @@ function convertComposerOptions<
     escapeParameter,
     messageResolver: options.messageResolver,
     inheritLocale,
-    translateExistCompatible,
     __i18n,
     __root,
     __injectWithOption
diff --git a/packages/vue-i18n-core/src/warnings.ts b/packages/vue-i18n-core/src/warnings.ts
index d24c38b74..c294abb34 100644
--- a/packages/vue-i18n-core/src/warnings.ts
+++ b/packages/vue-i18n-core/src/warnings.ts
@@ -8,9 +8,8 @@ export const I18nWarnCodes = {
   FALLBACK_TO_ROOT: code, // 8
   NOT_FOUND_PARENT_SCOPE: inc(), // 9
   IGNORE_OBJ_FLATTEN: inc(), // 10
-  NOTICE_DROP_TRANSLATE_EXIST_COMPATIBLE_FLAG: inc(), // 11
-  DEPRECATE_TC: inc(), // 12
-  __EXTEND_POINT__: inc() // 13
+  DEPRECATE_TC: inc(), // 11
+  __EXTEND_POINT__: inc() // 12
 } as const
 
 type I18nWarnCodes = (typeof I18nWarnCodes)[keyof typeof I18nWarnCodes]
@@ -19,7 +18,6 @@ export const warnMessages: { [code: number]: string } = {
   [I18nWarnCodes.FALLBACK_TO_ROOT]: `Fall back to {type} '{key}' with root locale.`,
   [I18nWarnCodes.NOT_FOUND_PARENT_SCOPE]: `Not found parent scope. use the global scope.`,
   [I18nWarnCodes.IGNORE_OBJ_FLATTEN]: `Ignore object flatten: '{key}' key has an string value`,
-  [I18nWarnCodes.NOTICE_DROP_TRANSLATE_EXIST_COMPATIBLE_FLAG]: `'translateExistCompatible' option will be dropped in the next major version.`,
   [I18nWarnCodes.DEPRECATE_TC]: `'tc' and '$tc' has been deprecated in v10. Use 't' or '$t' instead. 'tc' and '$tc’ are going to remove in v11.`
 }
 
diff --git a/packages/vue-i18n-core/test/issues.test.ts b/packages/vue-i18n-core/test/issues.test.ts
index c59ddb0b6..ed9fef922 100644
--- a/packages/vue-i18n-core/test/issues.test.ts
+++ b/packages/vue-i18n-core/test/issues.test.ts
@@ -1268,75 +1268,6 @@ test('issue #1717', async () => {
   })
 })
 
-test('issue #1738', async () => {
-  const resources = {
-    en: {
-      messages: {
-        common: {
-          actions: {
-            cancel: 'Cancel'
-          }
-        }
-      }
-    },
-    nl: {
-      messages: {
-        common: {
-          actions: {
-            cancel: 'Cancel'
-          }
-        }
-      }
-    }
-  }
-
-  function loadTranslations(): Promise<typeof resources> {
-    return new Promise(resolve => resolve(resources))
-  }
-
-  function delay(ms: number) {
-    return new Promise(resolve => setTimeout(resolve, ms))
-  }
-
-  const i18n = createI18n({
-    locale: 'nl',
-    legacy: false,
-    translateExistCompatible: true,
-    fallbackLocale: 'en',
-    missingWarn: false,
-    silentFallbackWarn: true
-  })
-
-  const App = defineComponent({
-    setup() {
-      const { mergeLocaleMessage, te } = useI18n()
-      onMounted(() => {
-        setTimeout(async () => {
-          const data = await loadTranslations()
-
-          for (const key in data) {
-            // eslint-disable-next-line @typescript-eslint/no-explicit-any
-            const { messages } = (data as any)[key]
-            mergeLocaleMessage(key, messages)
-          }
-        }, 100)
-      })
-      return { te }
-    },
-    template: `<div>
-  <p id="te1">{{ te('common') }} - expected true</p>
-  <p id="te2">{{ te('common.actions') }} - expected true</p>
-</div>`
-  })
-
-  const wrapper = await mount(App, i18n)
-
-  await delay(110)
-
-  expect(wrapper.find('#te1')?.textContent).toEqual(`true - expected true`)
-  expect(wrapper.find('#te2')?.textContent).toEqual(`true - expected true`)
-})
-
 describe('issue #1768', () => {
   test('Implicit fallback using locales', async () => {
     const mockWarn = vi.spyOn(shared, 'warn')
diff --git a/packages/vue-i18n-core/test/warnings.test.ts b/packages/vue-i18n-core/test/warnings.test.ts
index 3211a6b50..c4acb45f8 100644
--- a/packages/vue-i18n-core/test/warnings.test.ts
+++ b/packages/vue-i18n-core/test/warnings.test.ts
@@ -1,5 +1,5 @@
 import { I18nWarnCodes } from '../src/warnings'
 
 test('I18nWarnCodes', () => {
-  expect(I18nWarnCodes.__EXTEND_POINT__).toBe(13)
+  expect(I18nWarnCodes.__EXTEND_POINT__).toBe(12)
 })
diff --git a/packages/vue-i18n/src/vue.d.ts b/packages/vue-i18n/src/vue.d.ts
index 88ec73ede..ec7a45ae8 100644
--- a/packages/vue-i18n/src/vue.d.ts
+++ b/packages/vue-i18n/src/vue.d.ts
@@ -718,7 +718,7 @@ declare module '@vue/runtime-core' {
      * @param key - A target locale message key
      * @param locale - A locale, optional, override locale that global scope or local scope
      *
-     * @returns If found locale message, `true`, else `false`, Note that `false` is returned even if the value present in the key is not translatable, yet if `translateExistCompatible` is set to `true`, it will return `true` if the key is available, even if the value is not translatable.
+     * @returns If found locale message, `true`, else `false`, Note that `false` is returned even if the value present in the key is not translatable.
      */
     $te<
       Key extends string,