Blackout and TFM are definitely the "least" critically acclaimed of those but its hard to compare since pop albums are a lot "cooler" for critics to like nowadays.
Fame Monster, Born to Die, and EMOTION deserve at least some of their acclaim. 21 and Blackout get credit for being different from popular music at the time. Beyonce gets some credit compared Beyonce's previous material and its autobigraphical slant.
1989 is nothing but a generic, trend chasing sell out album where all the songs could be sung by Carly or Katy and be no better or worse.
The Fame Monster so easily. It's dated and just generally awful. Of the singles, Telephone and Alejandro are still great. I also love SHICD and... Dance In The Dark is nice. The rest is mediocre or just plain terrible (Monster and Teeth)
Blackout is a really good pop album for bops but pales in comparison to In The Zone in every way. Still in her top 3 albums.
Likewise 4 > BEYONCÉ but self titled deserves all of its praise, it's an incredible R&B album with a lot of depth and all the videos we got and the one liners it gave pop culture have been an added bonus.
21, Emotion and Born To Die are also great. 1989 is very overrated but has good songwriting and one of my favourite pop songs Style so it's probably second place