Were you going to use a mobile router or just a smartphone?
I tested a 942L with my Galaxy S9+ (Android 8.0.0) - T-Mobile. Created a hotspot and it works but video is slow. Went to mydlink.com and there was about a 10 second delay. Live video was a bit choppy.
Cameras can use a bunch of bandwidth so watch the data use on your T-Mobile plan. With the "unlimited data plan" you only get 2GB of hotspot data. I know they have hotspot plans you can pay extra for.
To limit bandwidth, do not register the camera with mydlink unless you want/need to use the mydlink lite app and/or mydlink.com portal. You will not get push notifications but email notifications will work. Watching live video or viewing from the SD card will use the most bandwidth of course.
Unfortunately I have not tested emailing a snapshot yet, but motion detection did send my push and email notifications pretty quick.