Something like `ssh -vvv user@host` would probably be useful to see where the key negotiation breaks for you, but it is unlikely to be a problem with git. My guess is that your host key is still using RSA with SHA1 and you haven't updated it by following the instructions[1] OpenSSH provided with their 8.3 release Carlo PS. I upgraded to OpenSSH 8.8p1 and had no problems connecting, but I am not on Arch, so that might be another possibility [1] https://lwn.net/Articles/821544/
