Two station buildings were awarded prizes in The Architects' Journal "Retrofit Awards 2019". I don't think this counts as "heritage railway", as neither has a railway function nor a heritage line.
One of them is
Bat & Ball, done up by Sevenoaks Town Council as a community resource. What's odd about this is that the Southern station exists beside it as a resolutely buldingless halt.
The other one is the
Engine Shed, repurposed for the Students Union of the University of Northampton as part of their Waterside Campus.