There are already very good, detailed instructions for upgrading mariadb.
support.plesk.com
What would be of interest to me would be whether you carry out a direct update from 10.1 to 10.4 or whether you carry out the instructions several times in succession, i.e. 10.1 to 2 to 3 to 4?
Is there any experience in this regard?

How to upgrade MySQL 5.5 to 5.6/5.7 or MariaDB 5.5 to 10.x on Linux?
Applicable to: Plesk for Linux Question How to upgrade MySQL 5.5 to 5.6/5.7 or MariaDB 5.5 to 10.X on Linux? Answer This article provides instructions for upgrading MySQL 5.5 to 5.6/5.7 and Mari...
What would be of interest to me would be whether you carry out a direct update from 10.1 to 10.4 or whether you carry out the instructions several times in succession, i.e. 10.1 to 2 to 3 to 4?
Is there any experience in this regard?