Well WereLeaf and Mobian Leaf are essentially the same person (unless ya meant Anthro Leaf, different style and continuity.) Assuming Leaf's werefox form was a separate entity from Mobian Leaf (maybe cloned, who knows) in terms of statistics, Leafvee doesn't stand a chance and will be stomached easily. Mobian Leaf has a lil more mobility than WereLeaf, but his Werefox form has more strength and probably to some extent more durability.

In short, regardless of who samples whose soles, WereLeaf will devour them both easily and can sample their soles during the swallow. The only way Leafvee is sampling soles is while he's pinned underfoot by either predator, and if it works out differently, Mobian Leaf might get to sample Leafvee's while consuming Leafvee, but not long after will he get eaten by his lycanthropic counterpart. Not saying it's impossible for Leaf's fox form to devour his werefox form, but honestly, I'd say it's a flat d20 roll with a high DC to meet. Basically, the odds aren't in favor of fox Leaf getting the upper hand on werefox Leaf.

So actual Werefox Leaf will come out on top either way, to face the mysterious CHALLENGER because I think a champion was found between the competitors here already.