do you suggest i use mariadb 10.4 or i should install mysql 5.7 ?
Neither.
I've had some troubles converting from mysql 5.7 to mariadb. This should not happen anymore but it's totally not needed to convert if you're switching servers.
Firstly, decide what you want to use on the new server, either Mysql or MariaDB.
If mysql then also install mysql 5.6 on the new server, transfer accounts by using admin backup/transfer and you should have no issues. Upgrade to 5.7 afterwards via custombuild.
If you want to use MariaDB, do -not- upgrade to mysql 5.7 but keep 5.6 on the old server. On the new server, install MariaDB 10.0 and you can easily transfer the account the same way.
This way you do not need to convert anything manully so less risks.
If you upgraded already to Mysql 5.7 and you want to use Mariadb on the new server, you have to install Mariadb 10.2 on the new server, no older version.
If you want, you can upgrade from MariaDB 10.0 to MariaDB 10.1 and after that MariaDB 10.2 (best not upgrade from 10.0 to 10.2 at once).
That's how I would do it. But make a good decision first to either keep using mysql or go to Mariadb.
does directadmin work with mariadb great and stable ?!
Yes both mysql and mariadb run fine with Directadmin.
p.s. be sure to keep your admin backups until everything runs fine after transfer.