[Mayron]

Ok my finished code is there:

local f = CreateFrame("Frame")
f:RegisterEvent("ADDON_LOADED")
f:SetScript("OnEvent", function(self, event, addon)
	if addon ~= "ShadowUF" then return end
	self:UnregisterEvent("ADDON_LOADED")
	if ShadowUF.db:GetCurrentProfile() == "MayronUI" then
		BTL:Show()
		TL:Hide()
	else
		TL:Show()
		BTL:Hide()
	end
end)

But unfortunately the:

"BTL:Show()
TL:Hide()"

part never reaches as both of the frames are showing for some reason. I had to also change "ShadowedUnitFrames" to "ShadowUF" because for some reason it came up with a lua error saying that "db" is a nil value but with that instead I do not get any errors. Not sure what that's about. I will keep up the experimenting.