Hey there,
I work as a subtitler. For Premiere, the best way in my experience is to use Belle Nuit Subtitler to spot and translate your movie and then export an EDL and TIFF files. You then import the EDL into Premiere and link it to the TIFF files. It’s a pain in the rear, bit it’s the only solution I’ve found, until Premiere comes up with an easier way to handle subtitles in their future versions. It’s much easier with FC Pro and Avid.
Good luck,
Danilo at subtitulos.tv