Question about D-Link DWA-X1850

I'm sure it's also OK for connecting to your mobile phone. But you don't really need WIFI6 for that. WIFI5 sticks are also sufficient. I bought the device because I wanted to benefit from the connection options of my Swisscom Box4 and use the WIFI6 standard, which has advantages with several devices in the network.
You can also connect your PC directly to your mobile phone via cable and use it to access the internet ;)
Or get a smaller one like the D-Link DWA-131. You probably won't get more than 300 Mbit/s with your mobile phone anyway.

No problem. I connected my "D-Link WLAN-AX USB stick" to the Internet via my mobile phone (mobile hotspot and tethering).