You'll miss out of some easter eggs but otherwise you can play Automata first. The Replicant remake drastically improved its gameplay from the original, but it's still a bit of a slog. Plus, while both require multiple play-throughs to see the "true" ending, Replicant doesn't have a surprise "story part 2" like Automata does, so you'll actually be re-playing the second half of the game like 3 times.
Replicant DOES have the better main cast, IMO, and their personal stories will resonate more with most people compared to 2B/9S/A2, but in terms of raw gameplay Automata is just better in every way.
If you're going to play both anyway, play Replicant first so it doesn't feel quite like a downgrade in terms of gameplay. If you're really only ever going to just play one of them, play Automata.
"History Is Much Like An Endless Waltz. The Three Beats Of War, Peace And Revolution Continue On Forever." - Gundam Wing: Endless Waltz