So I had an idea. What about a category to get a kill with every character in an online ranked or casual match? It could also be restricted to base game roster and not dlc's so anybody with the game could do it with no extra cost. I plan on doing it regardless but I just figured it seemed like a cool idea people might enjoy.

There is no need for a category for online purposes. Remember not everyone is gonna have the internet to play online, people might only have enough to even upload a run. Plus if you did, you wont know who in the server your facing that either might be a easy match or sweaty player to destroy you. Very inaccurate especially for a timing purposes. So to answer your question, no