Suggestions by @madhatter

Tom Holland

as Albedo in Ben 10 Alien Force

Score: +4

Zendaya

as Katara in Avatar: The Last Airbender

Score: +1

Hayley Atwell

as Andrea Beaumont/Phantasm in Batman: The Animated Series

Score: +6

Asher Angel

as Hogarth Hughes in The Iron Giant

Score: 0

Vin Diesel

as Iron Giant in The Iron Giant

Score: +1

Scout Taylor-Compton

as Gwen Tennyson in Ben 10 Ultimate Alien

Score: +2

Tom Holland

as Ben Tennyson in Ben 10 Ultimate Alien

Score: +8

Christain Bale

as Ben 10,000 in Ben 10 Ultimate Alien

Score: -1

Robert Downey Jr.

as Professor Paradox in Ben 10 Alien Force

Score: +1

Jeff Bennett

as Azmuth in Ben 10 Alien Force

Score: +1

Mark Hamill

as Max Tennyson in Ben 10 Alien Force

Score: +4

Scout Taylor-Compton

as Gwen Tennyson in Ben 10 Alien Force

Score: -2

Tom Holland

as Ben Tennyson in Ben 10 Alien Force

Score: +8

Jackie Chan

as Jeong Jeong in Avatar the last Airbender live cast

Score: +1

Kevin Michael Richardson

as Lion Turtle in Avatar the last Airbender live cast

Score: +1

Mark Hamill

as Iroh in Avatar the last Airbender live cast

Score: -2

Scout Taylor-Compton

as Gwen Tennyson in Ben 10

Score: -14

Christain Bale

as Ben 10,000 in Ben 10

Score: -4

Shameik Moore

as Alan Albright in Ben 10

Score: -1

Woody Harrelson

as Thumbskull in Ben 10

Score: +2