I added a column to the Google Sheets file where I could 'tag' listed cards I had in-hand according to a sport - I'm always a 'baseball first' guy, but I want to account for cards from basketball, football, hockey, etc.
As far as cards from other sports, I'll have cards I'll physically add to the end of specific classifications / groupings that were made for my baseball collection - but there will also be a stand alone collection of cards for each sport.
Basketball - actual on court action - in the air; stick this with my baseball ‘in the air’ collection
Football - skill players - quarterbacks, receivers, running backs, tight ends
Football - special teams - running backs, defensive backs
Football - offense - kickers, linemen
Football - defense - cornerbacks, linebackers, linemen, safeties
Football - unique perspectives - celebrations
Hockey - actual on ice game action
Hockey - unique perspectives - celebrations, photo ops
Classifications / groupings for my stand alone cards may be just a little different from my baseball ones - I was trying to think of some unique themes for the football cards, but stuck with trying to arrange them by position.