Questions about Atra 6in1 Type C Stroke

I plugged the iPhone into the USB3 socket to charge it while the iPad is charging. This works.

It's not there because it's not necessary. I have never seen such an indication on any card reader, have you? The micro SDXC cards are available up to 2TB, so any reader with a corresponding slot should be able to read cards up to 2TB https://de.wikipedia.org/wiki/MicroSD

You can go for this one. Work just Fine. I think your S6 may not use the HDMI tho. Other functions should work regularly tho.

Yes, it only hangs on the plug. If you use it on an iPad, the black strip protects it quite well against "twisting".