Undertale:
OK, ignoring the cringe, the game has absolutely BEAUTIFUL MUSIC. If I had to choose, I couldn't, but I would have to go with a tie between MEGALOVANIA, It's Raining Somewhere Else, Battle Against a True Hero, and Another Medium.
Pokemon (All of the franchise)
I may be nostalgia blinded on this one, but ever since when I started playing Pokemon, all of the music was great. From the New Bark Town theme in HGSS, to the Ultra Space theme in USUM, I love it all. It's absolutely beautiful.
And finally, Sonic Forces.
This soundtrack is absolutely amazing. The game isn't perfect, but the soundtrack fits. Modern Sonic stage music is extremely fast paced. Classic Sonic Music has that Sega Genesis feel to it. And don't even get me started on how amazing the music for the avatar stages are. Overall, this is one of my favorite soundtracks of all time.