Slabbert rowed for Great Britain's women's eight crew at the Under 23 World Championships.
Budgett has earned all-conference acclaim from the CRCA for the second straight season.
Budgett, Edwards were tabbed as second-team All-America selections in 2019.
The Bruins' incoming class will enroll in the fall of 2019 and compete as freshmen next season.
Tuiasosopo and Tong have earned first-team All-Pac-12 Academic honors.
Budgett has earned all-conference acclaim for the second straight season.