Ok this one depends honestly cause I've heard it's hellish without a friend and I don't think I know anyone who'd be willing to tackle this beast with me.
Densetsu no Starfy
Kaze no Klonoa: Moonlight Museum
Ardy Lightfoot
Metal Slader Glory
Rhapsody II: Ballad of the Little Princess
Slime Mori-mori Dragon Quest 3: Daikaizoku to Shippo-dan