MySQL is a popular RDBMS (Relational Database Management System). MariaDB was born as a fork of MySQL.
Nowadays the two products are a little bit different. Migrating data from one system to the other could not be a trivial task.
MariaDB is fully GPLv2 licensed while MySQL has two licensing options, GPLv2 (for the Community edition) and Enterprise.
In the Fedora repositories you can find:
* MariaDB 10.3 (as a regular package or as a module)
* MariaDB 10.4 (as a module)
* MySQL 8.0 community edition (as a regular package or as a module)
NOTE: MariaDB and MySQL packages conflict each other. You have to install MariaDB or MySQL.
In addition you can install MySQL commmunity edition (8.0 or 5.7) from the repository maintained by MySQL itself: https://dev.mysql.com/downloads/repo/yum/