The British Board of Film Classification recently posted a detailed listing for trailers and other video content included with Mega Man X Legacy Collection 1 & 2. Looks like there's going to be all kinds of video content packed in along with the games. The full breakdown is below.
The Classification info also lists a July 19th, 2018 EU release date for the collections. This date is not officially confirmed by Capcom, so we can only take it as speculation at this time.