I'm looking for a plugin for my Minecraft server that creates and hosts a MySQL database so that other plugins that use a MySQL database can access a database in the plugin folder of the plugin I'm looking for.
For this you need a server on which the MySQL database is located, can also be the same on which the Minecraft server is running.
That doesn't make any technical sense.
Install MySQL / MariaDB on the server (or another) and configure your plugins on it.