I was just having trouble because you can’t use the same RSA key in order to connect to multiple accounts on bitbucket, this can be solved creating a new one, but you need to know how to handle them, and there is two ways to do it.
If you just need to connect with ssh to a host well you can just put it as a parameter, but this doesn’t work as a complete solution.
ssh -i PATH_TO_SSH_KEY email@example.com
This problem can be solved using a config file, for this solution you just need to create a file ~/.ssh/config and
Host shortname realname.example.com HostName realname.example.com IdentityFile ~/.ssh/realname_rsa User remoteusername Host bitbucket_1 bitbucket.org HostName bitbucket.org IdentityFile ~/.ssh/account1_rsa User git Host bitbucket_2 bitbucket.org HostName bitbucket.org IdentityFile ~/.ssh/account2_rsa User git
This way you could make, for example a clone in the following way:
git clone git@bitbucket_1:user/repo.git git clone git@bitbucket_2:otheruser/repo.git
And it works just fine with your multiple accounts.
Note: Keep in mind that according to that configuration, because two hosts share the same bitbucket.org alias if you clone from the real url, meaning firstname.lastname@example.org:something/repo.git it will use the later, in this case account_2 for the authentication. (You can obviously erase it from the Host tag, but this is just to explain the case)