I have just uploaded a new video about colourising black and white photos and videos using AI. I use two different programs, Adobe Photoshop and HitPaw video enhancer. I examine the results in EDIUS but these techniques can be used for any program.
If you are interested in trying out Hitpaw visit: https://www.hitpaw.net/hitpaw-video-enhancer.html
You can see it here: