Even so, he'd only aquire they're appearance, not their command of the force.
Seriously though, the Yeerks' aim was so bad when they were shooting at just animals, what hope would they have against Jedi, who can reflect dracon blasts back at the Yeerks, and force push anyone close to them. And even if a Yeerk were stupid enough to try and use a Bug Fighter against one, a strong enough Jedi could just take the Bug Fighter down.
If the Jedi were in place of the Andalites, the Yeerks wouldn't have even been able to take the Hork-Bajir.