Since the maximum number of people who can be teleported alongside me is about 10 people, it might be difficult to use Teleportation magic strategically to overturn a war situation.
However, you can use it to send in an elite unit or spies nevertheless. Additionally, the magic bag is attached to the magician who uses the Teleportation magic as well.
Thus it is usable for things like suppressing a local rebellion, arbitration in conflicts regarding territory and concessions, and subjugation of larger bandit groups.