Hi I've made a VoidChest plugin that is able to make use of both FactionsUUID & ASkyBlock which makes it easily useable for any server running either of these plugins.
This plugin allows you to have your players sell the items in a voidchest on a set interval
You are able to add any item you want to be able to sell in the Items.yml file
If you do not want the faction bank or the Island leader to get the money that is made with the selling of the items you are also able to set it so the block placer gets the money in the config if you desire to do so
If you are running a Factions plugin please enable econ (/f config econEnabled true)