[Fizzlemizz]

local self = {}

Is local to that chunk of code (in this case function) hence doesn't exist in the lower function and has not been passed to it. You would need too:

function CPA_Pokemon_Class:InitFight(table)
	for key, stat in pairs(table.stat.pv) do
		print(key, value)
	end
end

local table = CPA_Pokemon_Class:New()
CPA_Pokemon_Class:InitFight(table)

You don't really need all the [" "]

self.stat.pv = {
	stat = -- Int,
	EV = -- Int,
	IV = -- Int,
	reel = -- Int,
	reelactu = -- Int,
}

but that's entirely up to you.

I'm not metatable enabled so there is probably a more direct method using it.