tool tips for headers
 

Please let me know how to enable tool tips (longer description of what the header stands for)
K = strikeout
sorry i don't FIP, ERA +

Why would you remove the meaning of each column?

OSA?
BNN

19 versions and no definitions?
Confused

I can certainly see how this would be frustrating.
For the basic baseball acronyms one could of course google (or whatever search engine you prefer) and find these but there is also a nice glossary at the end of the OOTP manual (which, if you haven't found it, is a great resource to help answer many of your questions): https://manuals.ootpdevelopments.com...&page=glossary

Unfortunately, the glossary doesn't seem to include some of the game specific acronyms (like OSA, BNN, etc.) though these will be explained in the relevant portions of the manual.
OSA is short for OOTP Scouting Association.
BNN is, IIRC, the fictional news reporting agency that covers all things within an OOTP universe. Baseball News Network, perhaps?