I was watching Clone Wars today when this struck me. Was Echo meant to be a reference to the Marvel character Echo. They have the same name and iconic hand print. :
The Clones Are My Sons — Screenshots of Echo from Season 7's Unfinished...
ARC Trooper Echo - #VC176 | Rebelscum.com Forums
Clone Trooper Echo CW17 STAR WARS The Clone Wars TCW MOC | eBay
Target Exclusive Black Series Retro Card The Clone Wars ARC Trooper Echo Video Review And Images
Star Wars The Clone Wars Clone Trooper Echo Action Figure - TCW | eBay
Star Wars The Clone Wars Clone Trooper Echo Action Figure - TCW | eBay
Bad Batch Echo with Rex's handprint : r/StarWars
Echo | TCW Clone Trooper Wiki | Fandom
Echo | Filoni Star Wars Universe Wiki | Fandom
CT-21-0408 | Wookieepedia | Fandom
Amazon.com: Star Wars Clone Wars Animated Action Figure Clone Trooper Echo : Toys & Games
Echo TCW - RPG GM
Echo
Digital painting of Echo from The Bad Batch - really liking his armor design : r/StarWars
HASBRO Star Wars: The Vintage Collection VC#176 ARC Trooper Echo (T... — Aussie Syfi Collectables - Australia's True Home Of Star Wars Toys And Memorabilia