Plugin type incompatible with ESLint `defineConfig` type

[FloEdelmann]

Tell us about your environment

• ESLint version: 9.39.1
• eslint-plugin-vue version: 10.5.1
• eslint-plugin-vue-i18n version: 4.1.0
• Node version: 24.11.0

Please show your full configuration:

// @ts-check

import eslintPluginVueI18n from '@intlify/eslint-plugin-vue-i18n'
import { defineConfig } from 'eslint/config'
import jsoncEslintParser from 'jsonc-eslint-parser'

export default defineConfig([
    {
        name: 'i18n-json',
        files: ['locales/messages/*.json'],
        plugins: {
            '@intlify/vue-i18n': eslintPluginVueI18n,
        },
        languageOptions: {
            parser: jsoncEslintParser,
        },
        rules: {
            '@intlify/vue-i18n/key-format-style': 'error',
            '@intlify/vue-i18n/no-deprecated-modulo-syntax': 'error',
            '@intlify/vue-i18n/no-duplicate-keys-in-locale': 'error',
            '@intlify/vue-i18n/no-html-messages': 'error',
            '@intlify/vue-i18n/no-missing-keys-in-other-locales': 'error',
            '@intlify/vue-i18n/prefer-linked-key-with-paren': 'error',
            '@intlify/vue-i18n/valid-message-syntax': 'error',
        },
    },
])

What did you do?

Run npx tsc --noEmit

What did you expect to happen?

No type errors

What actually happened?

eslint.config.js:10:13 - error TS2322: Type '{ configs: { 'base-legacy': { parser: string; plugins: string[]; overrides: ({ files: string[]; parser: string; parserOptions: { parser: string; }; rules?: undefined; } | { files: string[]; parser: string; parserOptions: { ...; }; rules: { ...; }; })[]; }; ... 4 more ...; 'flat/recommended': any[]; }; rules: { ...; ...' is not assignable to type 'Plugin'.
  Types of property 'configs' are incompatible.
    Type '{ 'base-legacy': { parser: string; plugins: string[]; overrides: ({ files: string[]; parser: string; parserOptions: { parser: string; }; rules?: undefined; } | { files: string[]; parser: string; parserOptions: { ...; }; rules: { ...; }; })[]; }; ... 4 more ...; 'flat/recommended': any[]; }' is not assignable to type 'Record<string, ConfigObject<RulesConfig> | LegacyConfigObject<RulesConfig, RulesConfig> | ConfigObject<RulesConfig>[]>'.
      Property ''base-legacy'' is incompatible with index signature.
        Type '{ parser: string; plugins: string[]; overrides: ({ files: string[]; parser: string; parserOptions: { parser: string; }; rules?: undefined; } | { files: string[]; parser: string; parserOptions: { parser: string; }; rules: { ...; }; })[]; }' is not assignable to type 'ConfigObject<RulesConfig> | LegacyConfigObject<RulesConfig, RulesConfig> | ConfigObject<RulesConfig>[]'.
          Type '{ parser: string; plugins: string[]; overrides: ({ files: string[]; parser: string; parserOptions: { parser: string; }; rules?: undefined; } | { files: string[]; parser: string; parserOptions: { parser: string; }; rules: { ...; }; })[]; }' is not assignable to type 'LegacyConfigObject<RulesConfig, RulesConfig>'.
            Types of property 'overrides' are incompatible.
              Type '({ files: string[]; parser: string; parserOptions: { parser: string; }; rules?: undefined; } | { files: string[]; parser: string; parserOptions: { parser: string; }; rules: { 'no-irregular-whitespace': string; 'spaced-comment': string; }; })[]' is not assignable to type 'ConfigOverride<RulesConfig>[]'.
                Type '{ files: string[]; parser: string; parserOptions: { parser: string; }; rules?: undefined; } | { files: string[]; parser: string; parserOptions: { parser: string; }; rules: { 'no-irregular-whitespace': string; 'spaced-comment': string; }; }' is not assignable to type 'ConfigOverride<RulesConfig>'.
                  Type '{ files: string[]; parser: string; parserOptions: { parser: string; }; rules: { 'no-irregular-whitespace': string; 'spaced-comment': string; }; }' is not assignable to type 'ConfigOverride<RulesConfig>'.
                    Types of property 'rules' are incompatible.
                      Type '{ 'no-irregular-whitespace': string; 'spaced-comment': string; }' is not assignable to type 'Partial<RulesConfig>'.
                        Property ''no-irregular-whitespace'' is incompatible with index signature.
                          Type 'string' is not assignable to type 'RuleConfig<unknown[]> | undefined'.

10             '@intlify/vue-i18n': eslintPluginVueI18n,
               ~~~~~~~~~~~~~~~~~~~


Found 1 error in eslint.config.js:10

Repository to reproduce this issue