Time to accept 3 facts.
(1) Pranks is a Swordsman.
(2) Roger is a Swordsman & Pranks/Roger both use the same style of combat like Yamato/Kaidou.
(3) Mihawk's Swordsmanship > Roger & Pranks.
Mihawk was just not the Strongest Swordsman in Roger's Era, he is in Pranks' era.
Mihawk & Pranks being very close to Roger is a possibility now.