I found a collection of cheat tables on one of my hdds. But it was for Tears of the Kingdom. I'm not sure if
N.
is still running around Mugen Fighters Guild. But he helped make the tables. it's possible he might have something. I'll keep looking.

POINTERS!!

gah

OR A NIGHTMARE

The method that seems to be the easiest for people is to use only the darkest color for the sketch. Once you're happy you add the next layer of brightness. One at a time, up through the highlights.
Capcom and SNK both have "rules" you can follow to get their shading a little closer.

the thumb seems a little long

That's a char I haven't seen in a long while.

look up some of Inktrebuchet and Balthazar's spriting methods. I think balth has some really good videos on youtube so you can see what his actual method is.