Most TVs do not and will not support this.
Besides, LG has been caught and I didn't hear if they fixed the next issue.
Didn't LG or support tell you no?
I have 55LA6210 LG smart TV. I loaded all my movies on an external HD and connected it to USB.
If i put a single subtitle in the same folder with the same file name as the movie, then the movie gets displayed with subtitles.
but how can I load more than one subtitle for more than one langauge?
I tried to use the same filename with 2 letters language suffix like ".en" for English or ".ar" for arabic. but this is not working.