What kind of tablet are you using? Wacom tablets in particular seem to have a history of issues of not working correctly sometimes on Linux, there are other tablets that are Linux compatible, there's one tablet I've been eyeing recently and it's the XP Pen Tablets. Not saying you should get a new tablet, but to consider alternative options if the current tablet isn't working out.

I assume you're running Clip Studio and these other apps through Wine which isn't picking up the pressure sensitivity properly? Without knowing specific details on the tablet and such it's hard to determine how you would need to go about fixing it. Something else you could try is WinBoat, it's a very early beta application but you get the benefits of having a full Windows environment running on Linux as a VM in a Docker container allowing you to run apps natively and being able to do USB Pass-through for specific devices and you would only have to install tablet drivers on that for your tablet.

One other thing if you go to this here you can test the Tablet Pressure in your web browser. https://openprocessing.org/sketch/591905

i'm using a wacom mobile studio pro 16 which is a supported tablet. i've tried the tablet in clip studio, zbrush, and substance paint. no pressure sensitivity at all. but the sensitivity works on that website though. weird

If its working in the web browser that probably means your install of Wine for the application doesn't have the driver installed to support the tablet. How have you installed these applications? Did you use Lutris or some other?

If you used Lutris you can right-click the application and click the Wine glass icon and select Wine Control Panel and then select the "Add/Remove Programs" and install Wacom the drivers after downloading it.

If you installed through just Wine itself you will need to instead run Winetricks, select the default prefix when it shows you the menu and then click the "Run Uninstaller" to install the drivers that way.

i used lutris for them both. i tried installing the drives the way you said and it didn't work. i also tried installing winboat too but i can't install it since i can't get docker to install either. i might just have to say screw it and just transfer the files between the tablet and the desktop instead. the tablet has windows on it with zbrush and clip studio already on it. might be the way to go from here on out if i can't get this other stuff working

You use z brush and blender at the same time?