There's one hurdle before all of this can even be considered: the mogstation isn't connected to the in-game client. The in-game UI completely lacks cashshop elements, and your crysta balance isn't a viewable currency.

Also, this entire situation sounds like one big headache for Square-Enix. Black Desert Online does this legal RMT garbage where 90% of the cashshop items can be listed on the marketplace. I believe the items first started out where you could pre-order them, top order always won, then they changed it into a bidding system where RNG wins. Also, each item had a fixed price - unlike FFXIV where it's a completely free market.

RMT is frowned upon. Making it 'legal' shouldn't change that. It's the same shenanigans except now it's free2play-cashshop-greed shenanigans. You can argue all you want about how gil isn't being injected into the economy - that doesn't change anything. The fact is it still gives people the option to pay real world money for an in-game currency. That is pay to win.