I usually only place one bookcase for a residential lot since the game lumps all books together anyways.
I spent a few days trying to find a way to save a bookcase loaded with all the skill books so I can plop it down onto any Library lot but wasn't successful.
Instead used a mod that adds a debug cheat to add all books. It worked but hasn't been updated in a long while. It's possible it doesn't need an update but the creator also hasn't been around. I've since pulled it from my game but it's there if I need it.
Keep Books after Publishing is a great mod by scumbumbo currently being kept up to date by LittleMsSam. I've used this in the past but would rather make a copy before publishing so it's one less mod I need to worry about.
