vue-i18n.esm-bundler.js:46 You are running the esm-bundler build of vue-i18n.

package.json

"dependencies": {
+   "vue-i18n": "^9.1.6",
},

vite.config.ts

export default ({ mode }) => {
    const __DEV__ = mode === 'development'

    const alias: Record<string, string> = {
        '@/': `${resolve(__dirname, 'src')}/`,
    }

    if (__DEV__) {
        // 解決警告You are running the esm-bundler build of vue-i18n.
        alias['vue-i18n'] = 'vue-i18n/dist/vue-i18n.cjs.js'
    }

    return defineConfig({
        resolve: {
            alias,
        },
    })
}