Those are BTS interviews and they should be set as Featurettes:

Featurette

Any material that is not a trailer, a teaser (including TV Spots), a BTS footage or a clip, should be added as a featurette. This include BTS interviews (e.g. "Behind the Bricks" Featurette).

https://www.themoviedb.org/bible/movie/59f3b16d9251414f2000000a#59f73db79251416e7100001b

Then what exactly is "Behind the Scenes" a category for? The LEGO Batman featurette I'd obviously say is not a BTS, as it is in-character than actually about the production itself.