As this project appears to be fairly unknown in the fediverse still, I’d like to use this opportunity to advertise Flohmarkt. This Fediverse equivalent of Facebook Marketplace already has some instances up and running - see here: https://codeberg.org/flohmarkt/flohmarkt/wiki/flohmarkt-instances
It’s not that bad. It’s just German for flea market. And English speakers shouldn’t have an issue with at least “Markt”. Not far from a cognate.
Definitely better names but I think the bigger hurdle is getting the critical mass to get something like marketplace to work in the fediverse even with the perfect name.