I have 3 weapon sets under my favourites (Q):

1. Fine Dwarven Bow
2. two Fine Skyforge Steel Daggers
3. two Fine Scimitars

However, the game fails to understand/remember that i want to dual wield either 2 of these daggers OR 2 of these scimitars - when i press 2 (or 3) i ussually end up with the WRONG offhand, pairing up a dagger with a scimitar offhand OR a scimitar with a dagger offhand...

Is there any way to make Skyrim understand that when i press 2 i want BOTH daggers equipped, and when i press 3 i want BOTH scimitars equipped - without having these weapons mixed up?

Have you tried hitting the number for these weapons twice? That is usually what I have to do if I want to use two spells for magi characters.

^Hitting the number twice. That's how I dual wield.

It's a glitch with upgraded items. Happens to me on the Xbox all the time.

I am surprised something this basic is bugged, lazy bethesda hasn't fixed it since release?