I might throw together another true crossover one when inspiration strikes. In the meantime...
*Visser 3 is standing in the middle of the Yeerk Pool complex. The Animorphs are huddled behind a storage shed at the outer edge. The Visser knows they are there, but doesn't realize that they're human*
Visser 3: <Ah, the Andalite bandits, here in the Yeerk pool again. This time, however, you will not escape, because this time, I have coated the walls with powdered sugar! Furthermore, there are ants in my pants, and bees in my knees, I am told! If you could have seen...> *continues monologuing*
Ax: <We must escape. We cannot fight whatever giant alien creature the Visser will not shut up about becoming.>
Marco: Hey, no worries. I got this. *begins morphing something*
Rachel: Ax, chill. The guy's an idiot. A few slick moves and we're out of here like normal.
Tobias: <No, Rach, I'm with Ax. We can only have so many near-death experiences before one of us actually kicks the bucket. With our luck, it will probably come in some sort of preventable situation just before we're all clear and the war ends.>
Rachel: Pff. Wake up, Tobias. We're the good guys. That basically means we're all guaranteed happy endings.
Marco: Ready!
Jake: You morphed a little boy?
Marco: Oh yeah. Time to go kick some Yeerk butt. *Begins walking towards the Visser, cracking his fingers*
Visser 3: *stops mid-monologue* <What is this trick? I think I have the perfect morph for this occasion! I will burn you and slice you and dice you!>
Jake *muttering*: Sounds like my mom's cooking...
Marco: Really? You're going to fight me?
Visser 3: <You are an Andalite bandit. It is what must be done.>
Marco: Come on, man, I'm like, what, four years old?
Visser 3: <Probably closer to ten.>
Marco: Ohh, big difference. So you're going to beat up a ten-year-old and that's going to make you feel like some big, powerful villain?
Visser 3: <I... I guess not. Would you mind returning to your Andalite form?>
Marco: *shakes head* Not gonna do it.
Visser 3: <Then it appears we are at an impasse.>
Marco: Yep. I can't compete with you physically, and you're no match for my brains. And charm.
Visser 3: <You're that smart?>
Marco: Let me put it this way. Ever heard of Plato? Aristotle? Socrates?
Visser 3: <Who?>
Marco: Morons.
Visser 3: <Wait, go back. I'm an alien. Totally didn't get who those were.>
Marco: I believe our only chance now is a battle of wits.
Visser 3: <Seriously, this makes very little sense right now. I mean, I take it that those were smart people you just named, but how does any of this follow logically?>
Marco: To the death.
Visser 3: <Whatever. Let's just do this.>
Marco: *nods* Good. Then pour the wine.
Visser 3: <You're like four years old!>
Marco: Probably closer to ten. Pour it!
Visser 3: <This is absurd.> *pours one goblet and one bowl of wine*
Marco: Now, I'm going to add poison to only one of the containers of wine. The contest ends when you choose one, and we both drink.
Visser 3: <I am so lost. How did I get roped into this?>
*Marco walks over to the table and pulls something from his pocket, then turns his back towards the Visser, facing the wine. The Visser leans over, trying to get a glmpse of what's going on with his stalk eyes. Marco uses the taser he's just pulled from his pocket to tase the Visser into a twitching mess on the floor.*
Visser 3: <That is very clearly not poison!>
*the rest of the Animorphs cheer*
Visser 3: <Don't tase me, bro!>
Marco: *evil laugh, continued tasering*
Visser 3: <Aren't we at the Yeerk pool!? There should be literally thousands of other Controllers here! Why isn't anyone helping me!?>