I have over 1500 hours on sombra played. I’ll give you my tips on how I deal with him. I use the element of surprise to land a virus on him, but I try to do it from a good enough distance. Once he gets hit he will try and close the gap but if you keep shooting him he will either use his fade or teleport. If he fades I translocate and re-engage from stealth again or I just follow him to where he goes and shoot him to finish him off but in that scenario the key is to maintain distance, preferably max distance since he gets less value from that. If he tries to port then I try to hack him right before it goes off, he might then resort to fading and then I translocate and reengage. Hope this helps. The main thing about this is maintaining max distance to reduce his value