After February 2019 the Monthly PlayStation Plus Lineups will Consist only of Two Free PS4 games, From March 8, 2019 no More PS3 and PS Vita Games on the Service
PlayStation Plus' free offerings for PS4, PS3 and PS Vita go super indie - KnowTechie
PlayStation Plus dropping PS3 and Vita games in 2019 (update) - Polygon
PlayStation Plus for PS Vita Available Next Week – Take the Tour – PlayStation.Blog
Amazon.com: Ninja Gaiden Sigma 2 Plus - PlayStation Vita : Video Games