Monero

It has been around for a decent amount of time and from what I could tell had a decent reputation. It might have even been per order escrow but the market can still steal the money in escrow.

Something like the particl marketplace would be great for repeat small time buyers but for everyone else the collateral requirements are either too annoying for infrequent buys or too expensive for large deals.

Can't do 2-2 without collateral since the buyer has no incentive to release funds once they received their merchandise and even non malicious buyers would often just forget about it.