Question 1

Can I leave this plugged this into a TV (to display photo content) and then use the wireless capabilities to upload new content?

Accepted Answer

Unfortunately, no. It needs to be plugged in to charge up, then unplugged to connect to it wirelessly to copy your files, then plugged into the TV (or in my case, the digital picture frame) to use. Also, it requires a phone app to use it, and it can be a little flakey. Overall, I did not like the flash drive and do not use it as originally intended.
There are dual USB drives that better suited my needs. One end has a USB-C to plug into my phone and copy the pics, the other a standard USB to plug into my picture frame. There are ones with most any phone connection on one end, iPhones included, you just need to dig some to find them on Newegg.  An example of one is Newegg Item=N82E16820173153

Question 2

Can this be used as a USB storage inserted into 3d printer to transfer files wirelessly so I don't have to remove the drive to put new files onto the printer?

Accepted Answer

If printer has USB or is wireless it will let you transfer  files either directly from computer to stick ok wireless not sure how printer  connections are made.

Questions & Answers