Primarily, this library provides useful universal API TeleportUtils.teleportEntity(...) for teleporting many kinds of entities including player, animal and so on in one method with many options and consistency between those types.

Moreover, this library provides more powerful API TeleportUtils.teleportEntityWithItsPassengersLeashedAnimalsAndVehiclesRecursively(...) that makes teleporting with many other connected entities possible, including vehicles riding and animals with leads.

Finally for the proof of concept, this library provides command /teleportWith and its aliased version /tpw that makes teleporting with other entities possible. This has the same signature with the original /teleport and /tp command (as described in here) so it wouldn't be hard for the existing players to use.

Requires following fixes in order to work properly (they are from the same author):

Recently also added inter-dimensional equivalent APIs for the portal support. You can travel through portals while riding, with leashed animals.

Credits to:

blay09, since the codes here helped a lot in developing the core logic.
LordDeatHunter, since the codes here helped a lot in developing the core logic.

Teleport Utils