I usually setup a reverse ssh tunnel from the destination to a VPS I own. For example, you could setup a reverse tunnel to sshd on the destination, exposing sshd of the destination on the VPS, to which I ssh and specfiy the VPS hostname + the reverse tunnel port, which tunnels me ssh the destination host.

Also, if you can't open ports outbound at all, there's https://samy.pl/pwnat/ but it makes things very slow.