Why didn't Chibi-usa initially recognize Sailors Mercury, Mars, Jupiter, & Venus as her friends?
I asked a fan who is not part of this SE community this question and she responded:


  . . . you found loop holes in the anime. The whole thing in R where Chibi-Usa didn't know Sailor Moon was her mom, or the four senshi were her friends, the same as in the future was in my opinion, a horrible decision on the anime creators side. In the manga she knew before she even went back into the past that Sailor Moon/Usagi Tsukino and her mother was one in the same. In the anime all she knows is stories of a senshi called Sailor Moon in the past that her dad told her. The fact that the inner senshi of the past and future look exactly the same, have the same names, etc, is completely side stepped by the anime's production. Like really? Are we supposed to believe she's so stupid she couldn't put those two things together? But alas, they try anyway.


Her interpretation is that in the 90s anime, Chibi-usa did know the names and appearances of Sailors Mercury, Mars, Jupiter, and Venus in the 30th century before she time-traveled to the 20th century, and that failing to recognize them in the past is a plot hole.