(This ended up so much longer than I expected.)
Okay- I'll focus on the first four parts because that's where shit hits the fan this time.
First of all, Someone Please Help Yaretzi. This evil gentleman is trying to use the mask for evil and she can tell he's evil and lying and all of this is wrong help-
She tries to stop the mask from working on him with the patricide. Tries to stop the spikes. She is terrified of the idea of being stuck with him. Evil Jonathan reminds her of her death and Hello Trauma.
She's rescued by the end of the part by DIO temporarily, she talks to him before he vampires himself, and she... she doesn't stop it.
She doesn't like Joseph. She doesn't like Jonathan. She talked to Joseph before he was molded into what he turned into. Trying to steer him away. Ultimately it fails, and she is completely CRUSHED by this. Caesar steals the mask in an act of rebellion. She ends up with the Hamon Warriors and the Pillar Men.
...(I can't believe this of all aus is when I reveal the other aspect of Yaretzi's origin and connection to part 2.) Yaretzi's tribe is one of the places the Super Aja passed through. She met the Pillar Men. She was a child, who didn't know Hamon and cared a lot about the world around her, so she ends up at least not dead by their hands.
...then she got masked. Murdered, not turned. It's a Domino effect and her village is burned and eaten. The mask left in the rubble. So when she wakes up not in the base, with beings that are actually fighting the Joestars like Dio did, she's very, very happy to help.
Ida time. It's roughly the same, what happened to her. Except... no Vampire Ethel. She just gets killed protecting the castle like she did. So Ida fights, and fights, and fights until she can't. Escapes with her life, and a grudge. Teams up with the group fighting Jonathan and doesn't get to avenge her sister yet.
...she stays far more in contact with the others, this time around. She gets pulled on board for the Part 2 mess. Helping in the background and relaying information on now Jonathan fights. She wants to avenge her sister.
Then she meets Yaretzi. She'll fight for the ghost in the mask, too.
Arute is a strange case here. She likely gets called in because of being a warrior only. She doesn't meet Yaretzi until then because Yaretzi didn't mask-hop because the original one was still intact. So she's fighting to save the world and push back the threats. Likely ends up helping to found the equivalent of the Speedwagon Foundation, but in opposition of the Joestars because they freaking escaped again and dammit if she doesn't make it difficult for them.
She's around until the end. Hamon extended lifespan, baby! She's gonna kill a vampire and keep teaching Hamon. Probably helps find Dio and fills him in on how things went down. She also probably helped with the stand issue for everything. Fellow Feeling time, baby! Not gonna be there for the raid because she is half the duct tape on the foundation but she's there in spirit.
Now... Madoka and Kyuuma. These two change the most.
Madoka's part of the brainwashed camp. She turned to being a hired killer after Kyuuma disappeared (was taken in by the foundation in secret).
Got a stand and roped into the Joestar Plan. I imagine her stand stays the same as the original, her soul really wasn't changed. So, she keeps Ace of Coins.
Kyuuma would have been working with the foundation since she was a young teen. Her story fundamentally changes, but the people she's around stay the same.
She sticks with the minions until the big showdown, where she's able to team up with others to save Madoka.
I imagine she ends up a vampire still, but it's Yaretzi's advice, not Dio's fault. Now, she gets sent to Morioh. Because there's a lead one of the Joestars went there and if there is, she's going to raise hell. I imagine she ends up befriending some of the group.
(also Rohan keeps trying to use Heaven's Door on her and she is having none of that. There's Foundation secrets in there, dammit!)
I dub her new stand: The Calling, after The Amazing Devil's song.
Her official assignment is to invest the crime spike, and capture the arrow. Her unofficial assignment is to a. Beat the shit out of Jotaro, and b. Keep possible allies out of harm's way.
This is not easy at all. She's going to kill someone at this rate and Kira hasn't even shown himself.
Kyuuma needs a goddamn vacation and it's only June. Arute is her phone contact and she is on speed-dial because she has the braincells.
(Now, I need Yaretzi to have gotten emotionally adopted by DIO she deserves it- reunion hell yeah- she's there in the corner telling stories.)