AlmaLinux 8 or AlmaLinux 9

I want to do a fresh install of CWP, but I haven't decided between AlmaLinux 8 and AlmaLinux 9 yet.

I want to know what the default MariaDB version is for AlmaLinux 8. I need a MariaDB version above 10.5.

Also, I noticed that CWP based on AlmaLinux 9 is missing some features. Which features are those?

Additionally, I noticed that the installation page indicates “EL9 is in beta stage.” Is it suitable for use in a production environment?

I am running my servers on AL8 with MariaDB 10.11 LTS (I don't need/want the 11.x branch yet). I needed to run AL8 because it is FULLY compatible with CWP, esp. with regards to CWP account migration so I could move CentOS 7.9 servers to EL8 with a migration path forward to EL9. This will give me up to a few years (if I need it) to thoroughly test & deploy AL9 in my environment.
https://endoflife.date/almalinux

Starburst is running all his production servers on AlmaLinux 9. Yes, CWP is officially only in beta for EL9, but it is mostly generally working. What you wouldn't have in AL9 is the ability to do CWP->CWP Migration. Also, cgroups probably will give you trouble in AL9.
https://forum.centos-webpanel.com/centos-configuration/cgroups-don-t-work-on-almalinux-9/

For new servers, I would recommend AlmaLinux 9.
Mostly for longevity in the EOL.

Like @overseer mention, MariaDB should be updated to the LTS 10.11 version, unless you want to go with 11.x

AL9 is 95% production ready, if you need  something specific, then maybe AL8 would fit your needs better.

Thank you. I have decided to install AlmaLinux 9. By the way, how do I upgrade MariaDB?

https://www.alphagnu.com/topic/23-upgrade-mariadb-1011-in-cwp-centos-7-centos-8-stream-almalinux-78-rockylinux-78/
https://starburst.help/control-web-panel-cwp/control-web-panel-cwp-admin-tutorials/upgrade-mariadb-10-x-to-10-11-with-cwp-on-almalinux-9/