Serious British tobacco card collectors (as in, the collectors are British), are well aware of baseball cards due to the market value and no doubt know of the Wagner. So you might include non-baseball and non-sport card collectors as potential buyers.
I visited a London tobacco card collector (cricket to English non-sport) and he talked a lot on the site about Pre-War baseball tobacco cards, just because they're so well known and expensive. He wasn't a baseball fan, but he was a tobacco card fan.
Also, being a man of the world
, I can tell you that foreigners, especially Europeans, are interested in Americana, American history and culture.