Note for lost people

[Zeioth]

This project didn't solve my problem but pointed me out in the right direction; After adding this line to /etc/environment and exiting my sway session, the issue solved:

WLR_DRM_DEVICES=/dev/dri/card1:/dev/dri/card0

You may need to change the order of card1 and card0 in your case. Cheers.