Weapon swaps with limit 1 augments disable the other weapon

Not sure if this is intended but it feels like it shouldn't be, im playing a thorns build and both my weapon sets have the Saqawal's rune of the sky and Fenumus' rune of Agony as #% of damage as extra is one of the best ways to scale thorns. But as I have just found out having them both in different weapon sets blocks you from using one foe the weapons (appears to always be weapon set 2).

was curious to try this as well with two staves, both with +1 spell level runes

unfortunate that this doesn't work. hope this is not intended