Firefox would give me weird problems with teams in the past. Have not tried it in a while though. I’ll try it and if it works without problems now I’m happy to leave chromium behind.

For teams specifically I’m just using the web version with chromium. Installed as a chromium app so I have quick access to it and have it on my taskbar. Rest of Office 365 works just fine in any browser. (Outlook, SharePoint, Power apps etc) For OneDrive Sync you can use https://abraunegg.github.io/ which should work on most distros.

Take a look at simple Android TV boxes with a USB port. There are plenty of options and you can just install vlc on them