I vaguely recall owning an off-brand TTRPG about playing immortals from Highlander with the serial numbers filed off, I think the main setting was Atlanta, Florida, but I have no idea what happened to it.Not officially licensed, but IIRC back when the cartoon was on the air there was a fan created Gargoyles book for the Storyteller system that was passed around on the internet. I wish I still had a copy - I remember it being pretty good. But a lot of my old 90s downloaded fan creations succumbed to bitrot before I could get them off floppies and onto other media
(There was also a Highlander fan book for Storyteller. Which, honestly, felt like White Wolf really missed the boat in NOT licensing that franchise for an adaptation. A closer fit to their usual product than Street Fighter was at least).