Since the World Series, the Nats have brought in more than a few players for 1 year with a hoping they would have bounce-back seasons. While in 2020 and 2021, the idea may have been for these guys to contribute to contending, after 2021, it became more of a "pump and dump" strategy hoping to trade these guys at the trade deadline for prospects. Sometimes it worked, sometimes it didn't, but a few made a great impression while they were here and still have fans quietly rooting for them (or not against them as much as other villains)
I think the 3 that most come to mind in terms of less than a year would be Kyle Schwarber 2021, Jeimer Candelario 2023, and most recently Jesse Winker. Who is your favorite short-time ex-Nat? Is there another I've obviously missed? Should Dylan Floro be on the list?
Note - I've limited it to guys who were on-board less than a year. That knocks out Josh Bell, Trevor Williams, and Hunter Harvey.