Could one create a command block that causes a teleport transport station to be created? Teleport transports are a command block triggered by a stone pressure plate that uses the /tp command in a command block to send the player to a specific "grand central station", a return station should also be created to send the player back to a place nearby the sending station. The effect should be triggered using a specific gold tool.
Bit late with my reply here, but this is absolutely possible! It may be worth using the “data pack” functionality, but the primary data pack logic is commands at its core!
It’s not quite what you’re looking for, but my own Warp Pads and KawaMood’s Waystones both accomplish similar things, though without a central hub. Both are open-source. Your case would probably be easier, since you could store the destination alone rather than maintaining one or more lists of valid destinations.