[Eungavi]

To me, it seems like you are setting points of oUF object, not a power bar's.

local function SetupHealthFrame(self)
    if not self.settings.setupHealthFrame then return end
    self:SetSize(unpack(self.cfg.hsize))
    self:SetPoint(unpack(self.cfg.hpoint))
    self:SetScale(self.cfg.scale)
end
 
local function SetupPowerFrame(self)
    if not self.settings.setupPowerFrame then return end
    self:SetSize(unpack(self.cfg.psize))
    self:SetPoint(unpack(self.cfg.ppoint))
    self:SetScale(self.cfg.scale)
end

local function CreateStyle(self)
    SetupHealthFrame(self) ← passing oUF object
    SetupPowerFrame(self) ← passing oUF object
    SetupEvents(self)
    self.Health = CreateHealthBar(self)
    self.Power = CreatePowerBar(self)
end