Basically, in the May 2019 Artificer UA (Unearthed Arcana: the Artificer Returns), the Artificer got two mutually-exclusive ways to enhance a non-magical wand to improve the spells it casts: the Wand Prototype level 6 class feature of the Artillerist subclass (which lets you add your Int bonus to damage for one cantrip), and the Enhanced Wand Infusion, which grants you a +1 bonus to spell attack rolls.
Is it possible to “dual wield” wands so that you can benefit from both of these bonuses at the same time?
Best Answer
These features should be compatible, though there is some awkward wording
The first important thing to note is that the Enhanced Wand infusion doesn't require you to actually use the wand to do anything, it requires only that you are holding the wand when you cast a spell:
It's basically a prototype version of the wand of the war mage which has the same wording:
You don't need to use the wand as a focus or actually involve it in the spell in any way. Though one imagines that is the narrative intent, the rules only require that it's in your hand when you cast a spell. Wands generally being one-handed tools, you are free to hold something else in your other hand, such as another wand, and use that normally too.
You will need to keep in mind that you need a free hand to manipulate material components and/or provide somatic components for spells, though; specific wands might or might not count as an arcane focus depending on your DM's ruling, which could obviate the problem for spells with inexpensive and unconsumed components, but for spells with significant material components - or spells with somatic but not material components - you can't get around needing a free hand.
The Artillerist's Wand Prototype feature basically lets you create a magic wand that only you can use which you can use to cast a cantrip. As explored in this question, casting spells from magic items is in most respects the same as having cast the spell yourself - you get the benefits of class features and abilities that interact with spells you cast, and you should also get the benefits of magic items like the wand of the war mage.
The only issue I can see is that the Wand Prototype description doesn't actually state that you cast the spell using the wand, it says that:
But, keeping in mind that the Artificer is still UA material, I think this is an unintentionally awkward wording and using the wand prototype is not supposed to be different than casting a spell from a normal wand in such a manner; it should still count as you casting the spell for such purposes, and get the benefit of a wand of the war mage (or an Enhanced Wand made by infusion) if you happen to be holding one in your other hand.