From here on out "Esque" shall be used to refer to "Similar to the character referenced's move" "X" shall refer to "no ideas"
I assume you just mean the B moves.
Vine whip would of been able to work....If Leafs could learn it.
For Up B as a replacement I would suggest using wolf's Up B as a base for "Aerial Ace"
Side B
could stay razor leaf but I have a better idea for what to do with razor leaf. I'd turn Side B into something Marth/Roy Esque since Leafeon specializes in Blade attacks Via Leaf blade.
Down B would have to be something unique. Perhaps a short range (Like 1 character model short) razor leaf shot from both sides. Not sure how that would work in the air
Neutral B could remain as synthesis ---> Solarbeam or be changed into Energy ball. Leafeon wouldn't be getting charges from attacks though so I would rather change Synthesis to charge faster while weakening solar beams power and making it shoot straight forwards instead of a 45* angle.
The other things I have to mention.
Forward smash should be Link Esque, slashing twice, once with the blade on it's head and another with the blade on it's tail.
Neutral air would be Meta knight Esque.
This character could literally be built off of other characters
Fair ---> Link
Bair --->Lucas. Tail would be slashing instead of kicking. No spike. Bucking could also be used but that's more of a horse's trait
Uair ----> X.
Dair ---> Considering Marth Esque but not sure.
Ftilt ---> Quick slash with Leaf blade from the head. Probably Marth Esque
Utilt ---> X
Dtilt ---> Falco Esque. Not as much launch power.
Jab ---> Two slashes with Headblade, third would be with the tail blade
Fsmash ----> as referenced above, Link Esque
Usmash ----> Backflip tail slash.
Dsmash ---> Spinning slash. Probably Squirtle Esque, but sends enemies horizontally.
...That's all I got.