There is already Gothic Ches which is quite similar to Capablanca.
In fact, I understand Gothic Chess differs just by the placement of the pieces.
So, you can custom Gothic Chess to make Capablanca Chess on chess.com
But yeah, it would be fun to have some more good ready-to-play chess variants, like Capablanca Chess, or also Omega Chess or Shako for those I know a little.
Capablanca Chess and or an English version of Shogi would be a fun addition imo.
What do you guys think?