Suggestions by @wbb

Chris Hemsworth

as Stone Crandall in Australian Vacation

Score: +1

Leslie Mann

as Audrey Griswold-Crandall in Australian Vacation

Score: +1

Randy Quaid

as Cousin Eddie in Australian Vacation

Score: +1

Steele Stebbins

as Kevin Griswold in Australian Vacation

Score: +1

Skyler Gisondo

as James Griswold in Australian Vacation

Score: +1

Beverly D'Angelo

as Ellen Griswold in Australian Vacation

Score: +2

Chevy Chase

as Clark Griswold in Australian Vacation

Score: +1

Christina Applegate

as Debbie Griswold in Australian Vacation

Score: +1

Ed Helms

as Rusty Griswold in Australian Vacation

Score: +1

Keir O'Donnell

as Marvin Bush in 41

Score: +1

Bryce Gheisar

as Marvin Bush (child) in 41

Score: +2

Michael Stahl-David

as Neil Bush in 41

Score: +1

Montana Jordan

as Neil Bush (child) in 41

Score: +2

Josh Gad

as Jeb Bush in 41

Score: +1

Andrew Wilson Williams

as Jeb Bush (child) in 41

Score: +2

Ryan Kwanten

as George W. Bush in 41

Score: +2

Chandler Riggs

as George W. Bush (child) in 41

Score: 0

Glenn Close

as Barbara Pierce Bush in 41

Score: +1

Matthew McConaughey

as George H. W. Bush in 41

Score: +1

John Goodman

as Pacha in Kuzco

Score: 0