Yes!!! Brighton & Hove Albion in 1934,
Well socks really.
Worn for a one-off game against Bolton Wanderers I believe. The game was sponsored by a local company that sold tartan, as a publicity stunt the Albion wore Tartan socks to advertise the company. The early years of commercialism in...
It is certainly official, it's on the Scottish Government official tartan registry
https://www.tartanregister.gov.uk/tartanDetails?ref=11646
I was told about this particular tartan by a fellow flags enthusiast, who's wife is Scottish, quite a few months back.