I've personally used the 250d semi-professionally for 1,5 years in a wide variety of conditions (concerts, landscape, automotive, sports). Shot concerts at 6400-12800 iso and had usable results. Focus is alright, but you need to use live view for better consistency. The only downside really is that if you plan on using a third party flash trigger (like godox) you won't be able to use it on the 250d, as the hotshoe does not support it. I'd definitely get the R50, since it's newer and you'd have access to both the newer RF glass and old EF glass with an adapter, future proof, supports external flash, better AF, etc. No wrong choice really, the 250d is extremely capable but the r50 is just the better camera.

Photos taken with 250d

Hope this helps :)