From Adobe help concerning the latest update and hardware acceleration :
Hardware acceleration updates
Hardware-accelerated H.264 and HEVC decoding on Mac
Hardware-accelerated H.264 and HEVC decoding is now supported on MacBook Pro and iMac Pro machines with Mac OS 10.13. Hardware decode acceleration is automatically selected as the default option (Preferences > Media > Enable hardware accelerated decoding) in PremierePro on Mac if the hardware supports it.
Windows Intel Hardware Encoding for MP4/HEVC
Hardware acceleration is now available on Windows 10 with 7th Generation (or later) Intel® Core™ processors and Intel Graphics enabled.
If your hardware supports it, then Hardware Accelerated is enabled in the Performance menu of the Export Settings dialog box.
If your system hardware does not support it, the Performance menu switches automatically to Software Only.