Recently I have read the volume 91 again and find some interesting stuff, that can make sense when you know what happened or is going to happen.
Okiku is only one month in Kuri because she traveled from 20 years in the past
Reference from the thefts of food from the Heart Pirates
Otsuru did actually see Okiku using a sword (I think at least), she just doesn’t recognize her from the past
Okiku recognizing the alias of Ashura Doji? / Holdem thinks it was Shutenmaru’s group the responsibles of the thieveries, when it was actually Law’s crew (although I think Shutenmaru probably stole some food of the farm too)
Oda trying to hide from Okiku that Luffy and Zoro know Inuarashi and Nekomamushi / Also, trying to hide from the reader that Okiku knows them too
Okiku crying for revisiting Oden’s Castle (ruins). Remembering this happened just a few months before on her timeline
Kanjurou is the only one of the samurais behind something, indicating betrayal
Kanjurou’s birds going to inform Orochi right after their time leap
Kanjurou is the only one of the 5 that is not showing his face, again, indicating betrayal
And again, Kanjurou’s face is behind something
Ashura Doji clearly mentioning Oden right after his introduction as Shutenmaru
Jack telling Kaidou’s desire of having the knowledge of Ashura Doji, that supposedly, knows everything that happened on Oden’s journey (we already know that’s not the case)
Reference of the Oden’s hour long execution
Hope you have enjoyed!