No, that’s not what OP is asking for.
He wants to use multi-selection in the “collections” view mode of a library, which is not possible currently.
What you want to do, can be done already, by using multi-selection of movies/videos and albums or artists in the regular library view mode.
(You cannot put single songs into collections anyway).
If your videos are in MP4/m4v containers, you can fill the ‘Album’ meta tag of these files with the collection name. Plex will put them into a collection by that name, upon initial library scan.
