You can absolutely use Tailscale; your host in the unrestricted country needs to be set up as an exit node (CLI argument in Linux, or a menu option in the system tray in Windows.)
Then, your local machine needs to be set up to use that remote machine as its exit node. (tailscale up --exit-node=remote-tailnet-ip-here)
Ah, sorry I hadn't appreciated you were after split tunnelling... You can do this with Tailscale for services where you're connecting to a fixed IP/FQDN, which I think rules out torrenting/P2P unfortunately.
The only way I've seen to pass a specific app's traffic through Tailscale appears to be an Android exclusive feature.
If I'm wrong someone please correct me!