@Lena-Brey 1300 AC so if following how JP server does their currency that would be $13 USD. As for buying costumes through Microtransactions that probably won't ever be a thing unless NA changes how they do Scratches. There are special currencies called Star Gems which can get gotten but they aren't as common as other in game currencies. AC can't be farmed. Your best bet if you want a specific costume is either buy it from a player shop with Meseta or try your luck with AC Scratches.
I am very curious if they will change some aspects of how the AC Scratch works. If you recall over the last few years, console games have been under fire for "lootbox" style purchases that gamble real life money for very low chances of "good" virtual goods. NBA2K is the best example of a game that did it in the West and the people tried to get the government involved.
All the good are completely optional. There are zero items you get from it that affect gameplay in the way of disadvantages or advantages. So I don't think it will be affected like games from EA.