I can confirm that the MIG Switch does NOT work on the switch 2. I don't have an express card to try, but I think this suggestion is MIG Switch propaganda. The Switch 2 should have no way of telling what kind of SD card is in the MIG
This was tested with a newly opened Switch 1 game which was dumped immediately using nxdumptool using MIG's official recommended process. The Switch 2 is fully updated.
UPDATE June 10th, 2025: Migflash posted a video on their site of the system actually opening games using the migswitch. I eagerly await their update to test using only my own, legit game dumps to be able to test if I get banned.
UPDATE June 18th, 2025: My Switch 2 was banned. I did not even get to use the new MIG update. I was banned because of my attempt to use it on launch day. No other actions were taken since then. This means it might be possible to use the MIG without a ban if you only use it with the new MIG update. (I am not complaining. I fully expected to be banned. Just sharing a datapoint)