Remove Zorin DE and install mate

[Forpli]

Yes, it is possible to install MATE. You can take a look here:

[HOW TO] Install KDE (plasma), GNOME, XFCE, Cinnamon, MATE, Budgie, LXQt, LXDE and UKUI Dekstop Environments

I think based on the kernel available and the repos available to Zorin the version available via Synaptic Package Manager is 5.27 which I prefer over 6 because Tiled Menu by Zren (Win10). You might want to take a look at Q4OS KDE:

With removing gnome I'd be careful. I am not sure. If you make a new install it would be better to install Zorin lite and then switch to Mate.