Samsung - T7 1TB External USB 3.2 Gen 2 Portable SSD with Hardware Encryption - Indigo Blue

MAC or Windows it uses the exFAT file system which means no reformatting needed for each type of computer since it works seamlessly between them.

You can’t do that directly but you can through a computer, I.e. the SSD does not connect directly to the iPhone but to the computer. You connect the iPhone to the computer, the SSD to the computer, and then transfer the files to the SSD just as if you were transferring to the computer’s internal hard drive.

I am currently using it without encryption on both my phone and computer.

It should work. I have used a Samsung t7 to backup my MacBook Pro and have been able to boot from the backup.

As of April 2021 update, can move PS5 games to it but have to move it back to play. Can play PS4 games from the drive