For the SGC 1910 entries, you just have to either refer to the checklists, or memorize them. The two 350 backs are mutually exclusive (there are no poses in the set that were printed with both a AB350w/frame and AB350nf back). There are a few players who have one pose in each subset, so that could be tricky if the SGC entry just gives the player name and not also the pose.
These 6 players have a pose in both the AB350w/frame and AB350nf checklist:
Bender
Doolan
Mullin
Pfeister
Street
Willett
Mullin and Willetts poses should be distinguishable from each other because the names are spelled differently.
Here are the checklists:
https://t206resource.com/American%20...Checklist.html
https://t206resource.com/American%20...Checklist.html