That's a hard one. Best that isn't Elgato? I've never had any real luck with other cards. I've used AverMedia cards in the past and had lots of problems with them. Conversely, I've never had issues with the Elgato cards, even the old ones.
I also bought one of the cheap ones off Amazon, it runs a bit hot but works fine.
However, why do you need it?
Mine was just to connect my Sony A6400 to my Mac, but in the last couple of months Sony have released software allowing direct connection bypassing the card. I know that Cannon has similar software and no doubt the others
A lot of big camera companies have been releasing software to allow your camera to be used as a webcam indeed. FujiFilm too. Not sure how well they all perform but it's def. more than nothing.
Some of the affordable capture cards on Amzon have a ton of great reviews so you can give it a shot and if it's crap just return it.
Personally, I have the Elgato CamLink 4k - but I know you were asking for non-Elgato brands. Two interesting bits of trivia:
Capture cards that DON'T do 4k are often faster (lower latency). For example the original CamLink was lower latency than the CamLink 4k. So if you are streaming in 1080p, it can be just fine to grab an older elgato used!
Similar to above, some cheap off-brand 1080p USB HDMI capture dongles are faster than the Elgato CamLink 4k and can be found cheap on Amazon.