According to SegaBase, there's...
AD&D - Eye of the Beholder (USA)
Dark Wizard (USA)
Dune (USA)
Dungeon Master II - Skullkeep (USA)
Heimdall (USA)
Lunar - The Silver Star (USA)
Lunar 2 - Eternal Blue (USA)
Rise of the Dragon (USA)
Secret of Monkey Island, The (USA)
Shining Force CD (USA)
Snatcher (USA)
Vay (USA)
Willy Beamish (The Adventures of ...) (USA)
3x3 Eyes - Legend of the Divine Demon (JAP)
After Armageddon Gaiden (JAP)
Aisle Lord (JAP)
Burai - Yadama no Yuushi Densetsu (JAP)
Cosmic Fantasy Stories (JAP)
Daihoushinden (JAP)
Death Bringer - The Knight of Darkness (JAP)
Detonator Orgun (JAP)
Faeria (JAP)
Funky Horror Band (JAP)
Heroic Legend of Arislan, The (JAP)
Illusion City (JAP)
Laughing Salesman, The (JAP)
Magical Girl Silky Lip (JAP)
Mega Schwarzschild (JAP)
Might & Magic 3 - Isles of Terra (JAP)
Nostalga 1907 (JAP)
Psychic Detective Volume 3 - Aya (JAP)
Psychic Detective Volume 4 - Orgel (JAP)
Record of Lodoss War - The War of Heroes (JAP)
Shadowrun (JAP)
Shin Megami Tensei (JAP)
Syndicate (JAP)
Some people might say Popful Mail (USA) is an RPG, in the same sense that Landstalker is.
Ranma ½ - White Orchid Serenade (JAP) might also be an RPG... SegaBase gives me an error when I try to access the page, and I haven't played far enough into it to do anything, just watched the intro.