Suns: Dillon Brooks
Grizzlies: Jae Crowder
Something like this makes the most sense for both teams IMO.
Both players are on expiring deals, Brooks offers much needed bench scoring for Suns. Crowder would be the starting forward for the Grizzlies and fits in perfectly with their grit and grind identity.
Grizzlies
Morant
Bane
Crowder
Jackson Jr.
Adams
Jones, Clarke, Williams, Green, Tillman
Suns
Paul
Booker
Bridges
Johnson
Ayton
Brooks, Payne, Saric, Shamet, Biyombo