What do you offhand with Main Hand slot dex weapons?

[Lorethys]

With every offhand I've seen so far needing Intelligence to equip, except for the shield which needs Strength, what is the purpose of one-handed Dexterity weapons?
Is there a useful reason to give up having a secondary attack? Or do the numbers get crazy enough where meeting the requirement of a non-primary stat just kind of happens? Is it even actually viable to, as an example, be a rogue running around with a spell focus? Or is that just a funny gimmick?

[Flash]

I think the devs are going for a hold dagger in main hand and the crossbow in offhand OR

if you have a main hand one handed dex weapons then u have the choice of equipping another off hand weapon or a shield and customizing ur character with a mix of strength and dex etc.