Yes and No. In the unmodded game the AI can use only two weapons (+point-defense).
If you talking about modded components, you can add a bogus ability to a weapon and use this to add the weapon to the design. I have done this in the Devnullmod for the monsters. They carry up to 4 or 5 different weapons on their designs and for example use the tractor/ripper/repulsor combo (rather make that tentacle/bite/spit-out
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).
I think it has been requested to be able to use more weapons for the AI, but it can't hurt to do it again.
Rollo