Dependency rules in a root eslint config

I have 2 projects with different .eslintrc config files. I created a root config file which merges all common rules. My issue is that my projects' rules have some rules based on dependencies like "@typescript-eslint/explicit-module-boundary-types".

My assumptions is it doesn't work from my root directory because it has no package.json/node_modules or some relevant files.

How do I make it work so that I could define this rule in my root directory?

My frontend code ignores the rule and complains about explicit-module-boundary-types. It works when I move the rule back to frontend's .eslintrc.

Here's my directory hierarchy:

project-root
├── frontend
│   ├── .eslintrc.json
│   └── .package.json
├── backend
│   ├── .eslintrc.json
│   └── .package.json
└── .eslintrc.json

root .eslintrc config

{
  "root": true,
  "rules": {
     "@typescript-eslint/explicit-module-boundary-types"
  }
}

frontend .eslintrc

{
  "env": {
    "browser": true,
    "es6": true
  },
  "parser": "@typescript-eslint/parser",
  "plugins": ["react", "@typescript-eslint", "prettier"],
  "extends": [
    "plugin:@typescript-eslint/recommended",
    "plugin:prettier/recommended",
    "plugin:react/recommended"
  ],
  "settings": {
    "react": {
      "version": "detect"
    }
  },
  "rules": {
    "react/prop-types": "off",
  }
}