Personally, I'll watch all shows involved with Crisis no matter how small. I think, not saying you should do this, a basic order is easy enough to do, and I know when the breaks between episodes of Black Lightning are and when the episodes take place, month based, thanks to you.
Here's my point, though. I'm sure anyone who wants to do the same would like a note at the top of the Arrowverse timeline stating which shows are in the CW Multiverse, in case they're as crazy as me to do such a thing, or just find it interesting.
Something like:
Shows that aren't technically in the Arrowverse, Earth-1 and Earth-38, but are in the Multiverse and do crossover are:
Batman (Earth-66)
The Flash (Earth-90)
Lois & Clark: The New Adventures of Superman (Earth-92)
Superman Returns (Earth-96)
Smallville (Earth-1001)
Black Lightning (Earth-18)
Messy multiverses, right?