This market resolves YES if an openly trans Republican is elected to a state or federal government position in the 2030 election or earlier. This market resolves NO if that does not happen.
It took them until 2022 to elect an openly gay non-incumbent Representative (George Santos, of all people...) and if you look at the "state-level offices" section of the Wikipedia page for "notable first LGBT+ politicians in the U.S.," the party affiliation looks kinda like D D D D D D D D D D D D D D R D D D D D D D D R D D D D D D D D D D D. Seems safe to say the base rate is really, really low.
Also, IDK what percentage of trans people are Republican at this point, but given what Republicans have been doing in Florida (and Texas, and Montana, etc. etc.), it's gotta be less than 10%. Maybe less than 5%...