Yeah, for Andrew and Sean to have practiced the Frolis Maneuver, they'd have to have learned it from a living Andalite. So, I'll make a character sheet for an Andalite character.
Name & age : Warrior Snopian-Lilifan-Asaerien (Approximately 25 years old in Human understanding of age)
Personality: Certain of himself, abrasive with most, extremely guarded, militaristic, purist.
Skills: Mastered the Frolis Maneuver. Moderate skill with Andalite computers, Abnormally strong (for an Andalite)
Likes: Food, Human "humor", killing Yeerks
Dislikes: Taking orders from Humans, Anything Yeerk related, Human arrogance, unprofessionalism
Relations with other characters: Comrades with Andrew, Connor, and Sean.
Backstory: Rescued by the "Animorph" team while being chased by the Veleek swarm creature. He initially helped them to repay the life debt created in that incidence; but now he's come to respect them all as fellow warriors. He still refuses to see any of them as his "Prince"; and will often bark orders at them as though he now held the distinction. Socially, the group seems decent, and they have often treated him to meals at establishments they call "bars". He's constantly annoyed at his Human comrades for calling him "Snoopy".
Morphs: Various Humans, Hork-Bajir, Kafit bird, King Cobra, Flea, Fly, Arctic Wolf, Golden Eagle, German Shepard, Tabby cat