I believe Weevil will be gifted a Devil Fruit so that he can grow to max WB power!
I am thinking it will either be some Scarab Zoan to multiply is superb strength a hundredfold making him the literal strongest next to Burgess and his strong fruit! He would have some buzz ability to disoriente foes. I'm kinda tired of zoans though, too many as of late but it would be a nice ref to his name and how Luffy
likes beetles
Another idea is for him to be the second Special Paramecia introduced!! Like Katakuri the paramecia will give him properties of a logia!!!! Logia intangibility is too good!!!
I strongly believe new DFs can manifest if thoughts and desires are strong enough and with Weevil childish desires + Bakkins obsession and greed + will of Whitebeard perhaps a special version of the Gura Gura will spawn from the heavens that will grant Weevil the power to turn into vibrations or sound and also control it, it wouldn't have the same dc or AP but its more tricky
A thunder thunder fruit (not lightning lightning)???