Gel discs over the blisters (under the socks) can be pretty helpful. My heel blisters caused by my old skates were gone fairly quickly after i started using them. You just have to make sure your socks fit snugly enough to hold them in place.
https://www.amazon.com/dp/B076PSX6FR/ref=cm_sw_r_cp_apa_glt_i_HG0CY95YEW50DM2FNJVH
I had something similar, though my issue is apparently down to boney ankles. I was eventually wearing the ankle padding on 1Xs (2 different pairs) to the boot of the skate and the guys at my local pro shop said it was going to happen with any skate as I just have boney ankles 🤷🏻♂️ You can’t really punch out boots of most skates in 2021 due to how they’re made now, so ankle pads/discs have helped immensely. I tried lots of different iterations of ankle pads and I’ve found these work the best https://www.amazon.com/dp/B076PSX6FR/ref=cm_sw_r_cp_api_glt_fabc_K68M9QHKGPPSCECH6A7G?_encoding=UTF8&psc=1
I second trying the Ez-fits: I typically need to use these silicone cushions https://www.amazon.com/gp/product/B076PSX6FR/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1
In addition to the ez fit neoprene sleeves https://www.inlinewarehouse.com/Ezeefit_2mm_Ankle_Booties/descpage-EZ2MMN.html
Just be aware that the Reign v3 and Myfit Crown liner are very different. The Reign's are much more compact and slimmer, the Crown's are like puffy little clouds on your feet, but will take up more space in your boots.
I've also had good luck using myfit fatboy liners for both my big wheel and aggressive set ups.
You might want to try the neoprene sleeves first then evaluate if you need a liner upgrade.