"Hey guys, look at Weevil, he can swing his bisento with the same force as Whitebeard in his youth, that means they are equal, ahahahaha, ihihihihihi"
In One Piece, physical strength is not the only factor that determines a character's power level or ability to defeat an opponent. There are several other factors that can give a character an advantage in battle, even if their physical strength is equal to their opponent. Some of these factors include:
Haki: This is a special ability that many characters in One Piece possess, which allows them to enhance their physical abilities and attack opponents. There are three types of Haki, the strongest being the Conqueror's Haki, which Whitebeard possessed and Weevil does not.
Devil Fruit: Many characters in One Piece have the ability to gain special powers by consuming a Devil Fruit. These powers can range from the ability to stretch like rubber to the ability to control fire. Whitebeard had a fruit with offensive abilities capable of destroying the world, something that Weevil does not possess.
Fighting Style: Each character in One Piece has their own unique fighting style, which can give them an advantage in battle. Some characters use weapons, some use hand-to-hand combat, and some use special techniques. Whitebeard used his bisento with Gura Gura something that Weevil cannot copy.
Intelligence and Strategy: Many characters in One Piece are able to outsmart their opponents by using intelligence and strategy in battle. Characters who are able to think quickly and come up with a plan on the fly can often turn the tide of a battle in their favor.
Experience: Characters who have been in many battles and have a lot of experience fighting can use this to their advantage in battle. They have more knowledge on how to fight and can predict the moves of the opponent.
All of these factors combined can make a character much more powerful than their opponent, even if their physical strength is equal. Physical strength is just one aspect of a character's abilities and in One Piece, it is not the only determinant of power or victory in a battle.