Is it possible to configure Plex to transcode SYNCed material WITH the .SRT subtitles hardcoded?

Hello there,
I have a sync problem for offline mode IF the .SRT file is separated the iOS app doesn’t play it for certain movies/tv series. The error message is the following “Something went wrong playing your media. Please try again.”
Therefore I would like to have a workaround, and transcode the .SRT file into the synced media for my phone.
And not having it as a separate FILE!
Is there any option? Even changing something deep in the PLEX config files…
Thanks!