I wanted so much to love these. I was also an early adopter - I followed every development for weeks and months and ordered them the first day the pre-ordered opened and got mine the first day they were available.
I also bought them specifically for Teams usage and I agree with you - they are completely unusable. There is a hissing/static at the end of anyone's voice and you cannot really fix or mitigate it. I tried two pairs and ended up returning them both. I also paired them with a Jabra bluetooth 5.0 link380 dongle to see if that helped, but the problem persisted.
Of course, there are already compromises with the low bit rate audio required by the handsfree profile mode in bluetooth, but these are the worst bluetooth device I have ever tried for calls (and I have tried many, many earbuds and headsets).
Do yourself a favor and do not buy these if you plan to use them for Teams.