Hi,
That is not determined by the device. The AR router is just a receiver, you should confirm with your LTE provider whether your SIM card supports the roaming.
Besides, you should beware of the LTE bands that your destination support. For AR502H, it supports LTE FDD band 1, 2, 3, 5, 7, 8, and 20. DO NOT bring it to the country in which the supported bands are not listed., else, you are just waste your time.