I hacked the eslint-plugin-php-markup package to make it work. The hacked code are available at here: https://github.com/dannyniu/eslint-plugin-php-markup along with a short guide on how to configure the eslint.config.mjs, here's an excerpt:

...
import html from "eslint-plugin-html";
import php from "eslint-plugin-php-markup";
...
... { files: ["**/*.php"],
  plugins: { html, php },
  processor: php.processor,
  settings: {
    "php/php-extensions": [".php"],
    "php/markup-replacement": {"php": "", "=": "0"},
    "php/keep-eol": false,
    "php/remove-whitespace": false,
    "php/remove-empty-line": false,
    "php/remove-php-lint": false
  },
} ...
...