Questions about Apple USB-C to SD Card Reader

Hello. No, it's for SD cards. It does not work for Micro SD

Yes

No, it has a usb-c connection and for the iPhone XS Max you need a Lightning connection.

Yes, the adapter can be used with the iPhone 15 Pro Max 👍

I can't say that, I use the adapter with the iPad.

I think you misunderstand or confuse Roman numerals with Arabic numerals: UHS-I and UHS-II vs. UHS-1 and UHS-3 The symbols used for the UHS speed classes are easy to misunderstand: While UHS-I and UHS-II refer to the bus speed, i.e. guarantee that the corresponding products achieve a data transfer between memory card and device of 104 (UHS-I) or 312 MByte/s (UHS-II), the labels UHS-1 and UHS-3 indicate the minimum speed at which data can be written from the device to the memory card: 10 and 30 MByte/s, respectively. The following applies: Devices that support UHS-1 or UHS-3 also support UHS-I or UHS-II.

Unfortunately, we cannot answer this question because we have not been able to try it out in such a form. However, I'll put the question in the community, maybe a user can help you :-)