There's a lot of questions about the following error, but they all have same solution which did not have any effect:
$ git push
Unable to negotiate with 192.168.XXX.XXX: no matching key exchange method found. Their offer: diffie-hellman-group1-sha1
fatal: Could not read from remote repository.
Please make sure you have the correct access rights
and the repository exists.
... in the ~/.ssh/config file:
## use kex algorithm ##
$ ssh -oKexAlgorithms=+diffie-hellman-group1-sha1
usage: ssh [-1246AaCfGgKkMNnqsTtVvXxYy] [-b bind_address] [-c cipher_spec]
Resolved by using this command I randomly found in some comment thread:
export GIT_SSH_COMMAND='ssh -o KexAlgorithms=+diffie-hellman-group1-sha1'
Must be called every time you open the Git Bash. Yeah, git is hell.