HDR movies crash beacuse you not enable it , its automatic enable which says ifallcon
but its not true , if you have 7.0 fimware check ps4 pro , hdr not working with 4 k , hdr working with 1080p , so its crash ,,
just go to image settings and advacne and enable hdmi 2.0 ( when a HDR video is opened in youtube or netflix)
Never faced any issues in 7.0 Nougat but i think it's more of an Android issue in Oreo Roms .. Something related with R/W Permissions.
The Stock Player has Lots of options but it always
1.mix-up/distort the subtitles except .srt and muxed ones
2.Failed to recognize the Atmos or TrueHD audio tracks
3.Always crashes the first time if you play any movie
But definitely an improvement over nougat video player..it now has adjustable aspect ratio and other useful video options..
Those 3 points can be ignored by using MX Player but NTFS Read is not supported by 3rd Party Apps(Using V528).