This is 25 yo Shanks, which means just a year before he made his base in East Blue(he was in East Blue for a year) and remember that just before that, on his way back to East Blue, he fought a Government Ship(with Who's Who) to take the gomu gomu no mi
So basically it means that at best it was around this time he was fighting Mihawk, with Blackbeard confirmed to have scarred him a year before that
Powerscaling wise, the daily duels hype between Mihawk and Shanks is not looking good
And after that, they grew seperately with Mihawk refusing to fight Shanks once more after he lost his arm, which basically mean there is even no way to outright prove who is superior
