A question about games that use Xwayland when I have monitors of different resolutions

I have two monitors, one is 4k and one is 1080p. Neofetch output shows my resolution as 1080p which I assume means that something using X (in fullscreen?) will be 1080p even on my 4k monitor. The main monitor is 4k and second monitor is 1080p under a Wayland session. Main monitor is scaled 200% and second is scaled 100%.

When I launch a game that uses X in fullscreen the resolution options only go up to 1080p even when it launches on the 4k monitor. I have two questions I guess. The first one is that if I launch it in windowed/windowed fullscreen will it be the correct resolution? The second question is, if the answer to the first question is no, what do I need to do to get the proper resolution to show up in the resolution selection menu in games that use X?

I have tried the xrandr --addmode stuff but apparently I did it wrong. If anyone has a good guide if I need to do that, I would appreciate it. I have also added the video=[display]:[resolution]@[refresh rate] kernel parameters for both monitors but it doesn’t seem to make any difference.

Thanks.