Hello there,
for documentation purposes (yes I like too view old gameplay videos and compare them to newer ones 
here are the B-Roll Videos I found on youtube
- E3 2016: https://www.youtube.com/watch?v=538mVlF46Kw
- Gamescom 2016: https://www.youtube.com/watch?v=koEDgem9aiQ&t=19s (with some extra artwork, I did not found only the b-roll)
- E3 2017: https://www.youtube.com/watch?v=RYKfmsv-lLY&t=1s
- Gamescom 2017: https://www.youtube.com/watch?v=nS3i-01MD3o&t=2s
- Unidentified: https://www.youtube.com/watch?v=kR5jTRIRjeI
I did not found b-roll footage for:
- E3 2015
- Gamescom 2015
- PGW 2016
- PGW 2017
- PSX 2017
@others: If you have some links be free to post them
@warhorse: Could you publish the B-Roll footage I know you have them in your archives 