It's hard to say for sure. Deku has grown a lot, but All For One is a powerful villain. It depends on various factors like their current abilities and the circumstances of the battle.
In 'All for One Deku' fanfiction, it's interesting to explore the new relationships Deku would form. For example, his interactions with villains who were once on the opposite side of him. Also, the power dynamics shift. Instead of being the underdog hero, he could potentially become a more complex and morally ambiguous character with All for One's powers. His internal struggle between his original self and the new, darker influence can create really engaging storylines.
The Devil Fruit in One Piece was a unique ability that allowed one to obtain various abilities by eating a specific fruit. The following are the names of all the demonic fruits and all the aptitude users in One Piece:
[1. Demon Fruit Name: Demon Slayer Fruit]
2. Ability User: Luffy (Monkey D Luffy)
3. Edible effect: It can grant the holder supernatural powers such as flying, rubber man, shrinking ground, demon wind kick, etc.
[4. Demon Fruit Name: Demon Lord Fruit]
5. Ability user: Usopp
6. Edible effect: It can grant the holder superhuman strength and speed, such as invulnerability, rubber man, jumping, etc.
[7. Devil Fruit Name: Devil's Fruit (Devil's Fruit King Fruit)]
8. Ability User: Choba (Chopper)
[Edible Effect: Grants the user animal-like characteristics such as cats, dogs, fish, etc.]
[10 Demon Fruit Name: Demon's Fruit (Demon's Kiss Fruit)]
Ability User: Franky
Edible Effect: Grants the holder the ability to swim, dive, etc.
[13] Demon Fruit Name: Demon Fruit (Demon Fruit of Demon Fruits)
Ability User: Shen Ping (Golovkin)
Edible Effect: Grants the wielder demonic powers such as fire, lightning, water, wind, etc.
[16] Demon Fruit Name: Demon Fruit (Demon Fruit of Demon Fruit of Demon Fruit)
Ability User: Brook
Edible Effect: Grants the wielder the abilities of animals such as dragons, snakes, birds, etc.
One Piece's Devil Fruit ability users were as follows:
1 Zoopa: It is a kind of food similar to glutinous rice. The fruit can turn into glutinous rice balls.
2. Namami: A type of wind fruit that can control the wind.
3. Usopp: A type of rock fruit that can turn into rock.
4. Ryu: A type of rubber fruit that can turn into rubber.
[5. Sauron (Shoulong): It is a type of sword fruit that can use all kinds of powerful swords in battle.]
[6 Sanji (Saiji): It is a type of demon fruit that can transform into a mermaid.]
[7 Robin (Nino): It's a magma fruit that can manipulate magma.]
8 Franky: It's a boatsmith's fruit that can control all kinds of boats.
9 Brook: A type of Netherworld fruit that can turn into a ghost.
Level 10 (Yoshi): A type of Wind Shadow Fruit that can control wind and shadows.
These are all the known Devil Fruit ability users in One Piece. There are also some characters that have yet to appear that have similar abilities.
If Deku had One For All early, it could either make him a hero sooner or cause him more problems. It might make his enemies step up their game or force him to face even greater threats. It's a fascinating what-if scenario that could go in many different directions.