@intlify/vue-i18n/sfc-locale-attr 
require or disallow the locale attribute on
<i18n>block
📖 Rule Details 
This rule aims to enforce the <i18n> block to use or not the locale attribute.
⚙️ Options 
json
{
  "@intlify/vue-i18n/sfc-locale-attr": [
    "error",
    "always" //"always" or "never"
  ]
}- "always"... The- <i18n>blocks requires the locale attribute.
- "never"... Do not use the locale attribute on- <i18n>blocks.
Examples of code for this rule with "never" option: 
🚀 Version 
This rule was introduced in @intlify/eslint-plugin-vue-i18n v1.3.0