Xiaomi
Does the Xiaomi 12 support eSIM?
No, the Xiaomi 12 has no eSIM and only works with a physical SIM.
The Xiaomi 12 does not have eSIM. For mobile data abroad you will need a physical (travel) SIM with this device, or roaming from your own provider.
Source: GSMArena
Check your Xiaomi 12 for an eSIM yourself
Dial *#06# on your phone. A 32-digit EID number means your phone has an eSIM. On iPhone check Settings > General > About; on Android check Settings > SIM manager.
Frequently asked questions about the Xiaomi 12
Can I use an eSIM on the Xiaomi 12?
No. The Xiaomi 12 is not eSIM-compatible and only works with a physical SIM. For mobile data abroad you'll need a physical travel SIM with this device.