Im wanting to build a General Grievous type character as a deadly inquisitor type villain, is there a type of talent that allows for an attack with two weapons then an immediate 2 weapon attack?

Nope but as it is a villain you can give it whatever you want. Either more attacks or perhaps give him the linked quality.

I agree with Jawa4thewin, you probably want to use linked. Also if the character has four arms you could give them the "free maneuver" talent that most four-armed species get.

In order to make villains a threat they need to have ludicrous stats, i'm talking 35 health and adversary 3 crazy

There are a couple species in the system that have 4 arms and it basically gives them their 2nd maneuver as a free maneuver. I just joined a game where I am playing an Ardennian (Rio from Solo) and the talent Frenzied Attack is what I use to represent the 4 arm attack.

[Suffer strain to upgrade the attach an equal number of times]

Using multiple weapons you then increase the difficulty of the attack appropriately and go crazy.

Easy solution that would generate a similar effect:

Some Nemesis are allowed to have 2 slots in the initiative, complete with action/maneuvers. One in a rolled-for slot, one at the end of each turn.

Give your dude all the normal benefits of 4-arms and then that Initiative option. He'd be able to do all kinds of crazy things like make two two-weapon attacks in one turn, but also wouldn't establish any kind of funky precedent for 4-armed characters your players might try to abuse down the road.

Use the rules for two weapon fighting, but allow for spending advantage for landing a third and fourth hit in the same way it allows for a second.