Print screen - cannot capture hand score total because is not updated to the 'live' video buffer (could you detect that keypress and put the frame on the clipboard instead?)
Xbox game overlay - if using a controller, hitting the key combo to take a screenshot using the xbox overlay will first enable keyboard/mouse which also hides things like tooltips (that you probably wanted to capture). Additionally the overlay seems to not work correctly in Balatro (or it complains about it not being supported, at least - something to do with the full screen method?). Recording works although you can't see the recording overlay or see the messages saying 'clip recorded' until after you alt-tab out.
Steam - seems to work afaik!
I am using Borderless mode so normally I'd expect all this stuff to work okay.