How to track where a bag is in HomeAssistant?

My son has a bag which he takes with him to Kindergarten every day. I'd like to throw in something like an Apple AirTag to be able to see where the bag is, but I have a couple of requirements:

• No subscription
• Should work in South Korea (AirTag does not work here)
• Sometimes it's me who brings hem to Kindergarten and I have a Android phone, sometimes it's his mom with a iPhone
• It should be somehow connectable to HomeAssistant as a device tracker to see where the bag is (or at least if it's at home or not)

Any ideas what would work?