Yes, you can use SD2Vita on a PSTV. If you have a USB drive that you can use and you haven't bought the adapter yet, then use the USB. The SD2Vita is a microSD to gaming card adapter that is inserted into the device's gaming card slot. It is recommended not to skip this section so that the change from the old main storage device to the SD2Vita is as easy as possible so that all applications can be transferred.
YAMT (Yet Another Mount Tool) is a multipurpose core add-on for PS Vita (TV) that allows a microSD card to be used as a storage device using an SD2Vita adapter.