I tried using Qwant recently but unfortunately the Swedish language results leave a lot to be desired. Much of the result are spam domains copying content just to get hits.
I hope it gets better, since I would really love a good European alternative.
Edit; oops, I thought you talked about both Apple and Android, I'm so used to ATV being Android tv.
I might leave the comment anyway if it helps someone else.
For Android tv, if using the official app, I would recommend downloading "Just (Video) Player" and then configuring the Jellyfin app to use external player.
On my Shield the videos play much better without transcoding
Make sure your computer is on a wired connection to your router if you don't have it like that. When I had my computer on wireless it often worked but it was a bit unstable. With the computer wired, it was solid.
So when I play I roll out the long Ethernet cable.
I see. Thanks for solving the little mystery!
That is a strange limitation though, and not something I would expect.