I have Now pluged in a 2 tb Seagate to my ps4, all Games from PKG hen section if i downloaded from here, i copyed to my old USB 2.5" 750gb that ist formattet with Windows in extfat and quickformat and USB 2.0 , clustersitze Automatic.
A lot of Files are big, FIFA 18, little big Planet etc...
I plugged the HDD to the left USB Port, activated hen from retrogamer via ESP Board, go to debug and Click on install all.... After 3 or 4 hours, i looked at my ps4 5.05 its all done (500gb games /42 title) and work perfectly.
I Hope its helped you a little bit.