You won't like the answer, as all of them are Exclusives. The Baroness is the only one of the four women that you can get a figure of that isn't an exclusive.
Starting with The Baroness, the best is the SDCC figure, which fetches like around $80 on ebay. It also features a head sculpt by Boss Fight Studios.
https://www.yojoe.com/action/13/baroness17.shtmlYour next options for her are her 25th figure, which is the same build as the SDCC version but with an older outdated head sculpt:
https://www.yojoe.com/action/09/baroness12.shtmlThen there's the 50th version, which is a re-release of the 25th version, but with worse paint apps:
https://www.yojoe.com/images/resize/w/MAX/imagestore/1806/75993.jpgWith Zarana, she was solely a SDCC exclusive and they released two different versions of her:
https://www.yojoe.com/action/11/zarana5a.shtmlhttps://www.yojoe.com/action/11/zarana5b.shtmlAs for Crimson Asp, she was a JoeCon Convention exclusive created for the purpose of reusing an exclusive head sculpt used to make Steel Raven. She costs a bit on ebay and I got her back when she was still affordable.
https://www.yojoe.com/action/13/crimsonasp.shtmlThe last one is Munitia, and she's not out yet. She's part of the Figure Subscription Service 8.0 and could only be bought if you subscribed to purchase 12 other figures. You have to buy her from a scalper once she comes out. Pic related is a prototype mock-up of her. I'd expect to pay to $90+ for her on ebay. Thankfully I subscribed.