all kidding aside, avoiding a 3 year commitment to Walker looks good, but Garcia for Lowe may not be the steal we thought it was. Right now, the Nats have a 0 fWAR out of 1B. That's 17th in MLB. Lowe himself is -0.1 fWAR.
I don't think there's a trade market for Lowe. I don't think any contender would view him as an upgrade.
Of the NL teams with > 5% chance of making the playoffs using FG's projections to date, the Reds (5.6% plaoyff odds,, -1.6 fWAR) and Giants (55.%, -0.9) have had the least 1B fWAR, with SD (43.9%, -0.5) also outfperformed by Lowe. It's mostly Arraez's D that's the problem, and I don't see them moving off Arraez; he's actually slightly above replacement individually (0.1) so Lowe's not a clear upgrade. Ian says the Giants more or less have an internal candidate in the minors, so I don't think you see Lowe dealt there. The Reds probably are too fringey to want to deal.
In the AL, Boston has made its move to backfill for Casas. Seattle could use an upgrade over Rowdy Tellez / Mitch Garver, but is Lowe an upgrade? royals have Pasquatch. He's had a down start, but it's not much worse than Lowe, and he's still making MLB minimum.
More or less, we probably are going to be stuck with Lowe at the trade deadline unless he kicks it into April levels again.