Okay, I've gone through all the weapons and added the "Article stubs" and "Articles needing images" categories as required. About weapon images: does it matter how much the weapon is upgraded to be considered for use in an image? If not, I may be able to provide some screenshots.
Well Vektor may be able to confirm it later, I don't think it matters what the upgrade level is. It needs to be an HD image - PS4 direct screenshot generates an image 1,920 × 1,080 - but 1280x720 might also be acceptable.
Also, I've been going through Special:Upload or Special:MultipleUpload and setting the attributes as best I can. When using MultipleUpload I can't set the Description field, but the others I set. See Y-09_Longbow_Synthesis.jpg for one I uploaded.
What I've been doing is using the Xbox to record a clip and then pulling a screencap from the video on Xbox.com. It seems a little convoluted to me; apparently they're adding a screenshot tool sometime this year.