Here's a large gallery of Beta screenshots from Vampire the Masquerade: Bloodlines.
A lot of these images are technically not Beta screenshots. They're from the released game, or a version close to it, and they don't feature anything not in the released game. The point is that most of them are screenshots taken by Troika themselves. I say "most" because I cannot prove for sure that all the pics I got from the Steam and GOG pages were taken by Troika. These are the largest resolution versions of everything I could find. I was unable to track down versions without third-party website's watermarks on them for everything, unfortunately.
Be warned that some of these screenshots show excessive violence. Blood, guns, and people being set on fire. Oh, and the body horror of the monsters Andrei created.
Something I learned while scouring the 'net for all this is that, back in the 2000's, game devs split screenshots like these between Online Only (for websites) and Print Only (for magazines). They made a habit of giving different screenshots to each group. I was unable to find a lot of the Print Only screenshots, so included scans of some magazine articles that include those shots.
archive.org was absolutely invaluable in recovering a lot of this. I sifted through most of the links from here.
Also went through this collection of articles on Bloodlines.
Lots of web- and reverse-image searches later, this is the most complete collection I could put together. Most of the original file names are lost. I named them Date-Location-Character(s). "UD" stand for "Unknown Date". The dates are the date on which they were uploaded to a website, which is presumably close to when Troika first released them.
