[Nanomani]

Try removing the movie from library from database before updating library.
That way it will always use local art.

If you refresh the movie after it has been already scraped, it will not default to local art but what has been brought back from the scraper before.

As this add on now allows the choice of poster or not, best way is to remove all movies from library and re-scan.
That way it won't bring back any posters at all.
And if you decide to refresh the movie after that, the poster will be set to the thumbnail of the movie instead and you need to select the local poster art yourself.
Yes this latter behaviour is strange but the only way to get local art is to remove the movie from the library and re-scan.
Try it.

If I scrape a new movie with his file srt :
GOOD => "strSubtitleLanguage" is not empty in table "streamdetails"
GOOD => all local Artworks are used

I use "update from internet" for an existing movie after adding a first srt subtitle file because :

If I actualise a movie with choice "Local" after added his file srt :
NOT GOOD => "strSubtitleLanguage" stay empty in table "streamdetails"
GOOD => all local Artworks are used

If I actualise a movie with choice "From internet" after added his file srt :
GOOD => "strSubtitleLanguage" is not empty in table "streamdetails"
NOT GOOD => all local Artworks are NOT used

I have post a issue about that behavour with subtitle file :
https://github.com/xbmc/xbmc/issues/22447

It is not realy a big deal. I'm probably making a mistake in understanding.
But all those behavior/logic is confusing to me.

Anyway thanks for your explain