AirPlay Subtiles Apple tv

So, I am using infuse 5 version with Apple TV 4th Gen and iMac 27" using plex . How I can get subtitles working on Apple TV over AirPlay? Subtitles is srt/video mkv file in same folders and named with same name but subtitles are not visible in infuse.
Thanks.

Unfortunately external subtitles won’t be available in Infuse when streaming from Plex (or other UPnP/DLNA apps).

If you are able to connect to your Mac via NFS, SMB, FTP/SFTP these files will be available.