[2019] Not sure how it happened, but I was able to pick up hero weapons as a Chitauri. Led to some awesome screenshots and probably some confused opponents...

That's an incredible screenshot!!!

However, do you mind reaching out to me via Live Chat and tossing me your in-game username and platform so we can grab your logs and investigate what may have allowed you to pick up Hero Weapons as a Chitauri? Additionally, do you remember what steps may have led to you being able to equip those weapons?