I have been lurking on a Marlins board ever since Realmuto was suggested over the offseason. Here is what I gather:
Realmuto is a slightly above average hitter who is on a huge hot-streak right now, inflating his value
Realmuto is an awful framing catcher
Anyone trading for Realmuto now would be overpaying for "over-performance". I think Realmuto is a really good get because you can expect a slightly above average bat, with decent mobility for a catcher, with decent defensive fielding value, who frames like a dump truck for the next few years.
Currently the Nats have a catcher who is "over-performing" his minor league stats, who is an adequately above average framer, who has above average defensive fielding value, and also has decent mobility for a catcher. I think you have to run Severino out there enough to see if his .351 BABIP starts to trend towards south of .300 which was his norm in the minors. If that happens, Severino is a backup and the Nats need a long(ish) answer at Catcher.
Maybe, but of active players with at least 425 games played over the last four seasons, only 53 have more hits than games played and an OPS above .750. The Nats have five of those 53. Murphy, Harper, Rendon, Kendrick and Eaton. Turner just missed the list because of games played. Realmuto is on that list, too.
