So basically, can you have it use like k1lly0us new filter api to check stuff like dlc ownership? So for example like if I have a shop that sells fireworks, only people who own the fireworks DLC can buy them.

Config for opening the specific shop could have an option like Requires DLC: "None"/"Fireworks" that checks it the player opening the shop has that DLC and if not relays the denial message.