[PAR35]

brace can be used incidentally as a shoulder stock, it is not design as such

That might work as long as you don't find yourself in front of a judge and jury with eyes and common sense.

[Manly Warrior]

Look it up friend, the law is the law. AFTE approves braces for AR pistols. Having a lawful weapon is an affirmative defense.

Common sense is not a criteria for the law or a jury, just the law as written.

https://www.guns.com/2017/04/25/atf-reverses-decision-on-ar-arm-brace/