I know some of the lost Wackys were done in Flashback II I believe, but in hindsight it would have made more sense to do a larger subset encompassing all of them, so as not to leave collectors pining for the rest in these ensuing years.
Not just in Wacky Pack Flashback 2, but more were done in ANS1 before that as well. That's what started the whole thing about the lost 1992 series Wackys finally being released.
After Flashback 2, a few others have been released on an on-and-off basis, but so far never to the same extent as those two series. And there's
still a lot more out there waiting to see the light of day officially. Some were finished and all ready to go before the series was cancelled; others were just roughs that never got beyond that point. To find out what they are, look up my post "Lost 1992 series Wackys that have been released and those that haven't been - yet." I'd also like to direct you to the Lost Wackys section of lostwackys.com, but I don't know how much of it is still operational ever since Rusty took ill. On my post, there's a reference to Fred Wheaton's article "Wacky Packages: The Lost 1992 Series," but it desperately needs to be updated in many places (I've given Fred all the updates it needs and so far they
still haven't been included). There's also a reference to a web article about Drew Friedman on my post, who was the artist who did much of the artwork for the Wackys that Pat Piggott painted for that series.