Whatever happened to the what-if stories?

I am completely 100% sure that I heard about this. At one point, there
was going to be a book series - may have been a collection of short
stories - which explored various 'what if' themes in Trek. Examples
being:

- what if Picard had been permanently trapped in the past (with Guinan)
in "Time's Arrow"

- what if Picard had never been rescued from the Borg and had been
Locutus permanently

There were lots of others, too, not just Picard stories. Whatever
happened to this idea? Why was it abandoned?

--
"Boom. Boom boom boom. Boom boom. BOOM. Have a nice day."
- Susan Ivanova, B5

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