I see a traditional SATA power connector inside, but no data. Is there anyway to hook up a traditional SATA drive to this? Even temporarily? I need to use my NUC to do something to a 2.5" SATA HDD
Cant use sata to USB cable as i need it to be bootable/show up in boot screen
If you can boot from bootable USB stick (and you can see such USB in the Boot Menu), are you sure that it will not be possible from you drive installed in SATA to USB adapter?
Each of the two M.2 sockets in this NUC includes support for a SATA lane. There are adapters that you can get that will expose this SATA lane using a standard SATA Data header. Here is such an adapter: https://www.amazon.com/NGFF-SATA-Converter-Adapter-Cable/dp/B0828TFFH1 (US$10).