This is a mod in which you can buy products in the market, it works absolutely in all modes and also has NBT support.
The server admin can add the product he has in his hands directly to the market. Specify the price and product ID, there is no need to add, correct or edit anything in the JSON file. Everything is done with commands from the server.
ADMIN COMMANDS
/mm add <category> <id> <price>
/mm remove <category> <id>
/mm create category <name>
/mm delete category <name>
/mm balance <player> add/set
/mm reload
PLAYER COMMAND
/shop