HDMI to DisplayPort Adapter, 6 feet Active 4K@60Hz HDMI to DP Braided Cable, Uni-Directional HDMI to DP with USB Power for PS5, Xbox Series X/S, Switch, PC, Laptop to DP Monitor, NVIDIA AMD

If it sounds you are having issues with HDMI 60Hz with the Nintendo. You can try the DP for the Nintendo but you need an ACTIVE adapter (HDMI to DP). https://www.amazon.com/dp/B0G8WT3PFB This claims to work with the Switch. You could then try using an A/B Switch. This would let you run both DP to a single port on your monitor. You'd have to just press a button to alternate between them.https://www.amazon.com/dp/B0CJT6JBM8 The only issue is that you are doubling up on adaptors here. I can't guarantee they will work. Try at your own risk Make sure you save your boxes and that you can return these items if they don't work for you!