Why write a list when I can just point you to one that overlaps with mine a lot? Apologies but no Spotify playlist here orz.
You can ignore the ordering–it is not important. I will just append some of the ones I enjoyed that were omitted:
- 700,000,000,000,000,000,000,000 no Sora de – Lights (Lapis Re:Light)
- Literature – Ueda Reina (Wandering Witch OP)
- Holy Passion Roses – Horie Yui, Matsuzaki Rei (Princess Connect! Re:Dive)
- Daddy! Daddy! Do! feat. Airi Suzuki – Suzuki Masayuki (Kagyua-sama S2)
- Goodbye Seven Seas – Jun Maeda x Yanagi Nagi (Kamisama ni Natta Hi)
- Geki! Teikoku Kagekidan Shinshou – Sakura Ayane & Shin Teikoku Kagekidan (Shin Sakura Taisen OP)
- Koori no Torikago – Amamiya Sora (Kimi to Boku no Saigo no Senjou, Aruiwa Sekai ga Hajimaru Seisen ED)
- Fascinate – Velvet Rose (IDOLM@STER Cinderella Girls) – Technically 2019 even though the CD came out in 2020. I just didn’t know about this song until 2020. Would have put it up in the previous section otherwise.
- WOW WAR TONIGHT ~Toki ni wa Okose yo Movement~ – Mizuki Nana, RACHELL (D4DJ First Mix) – This cover is historic. Also I love the DJ WILDPARTY reference animation, it feels just like the real thing.
- Kimi ni Aeta Hi – Itou Miku, Kito Akari (Adachi And Shimamura OP) – A proper seiyuu duet.
- Parade d’amour – Opera Seria Kiramekiza (IDOLM@STER Million Live) – Managed to channel chills for me the same the way as Generations 04.
- Hyakka wa Gekka ni Chirinuru wo – Hanasakuya (IDOLM@STER Million Live) – Appropriately time froze for me in that January weekend, and maybe for the rest of Million Live kingdom.
- Kiseki no Kane (Taisho 29 ver.) – Shin Teikoku Kagekidan (Shin Sakura Taisen) – This song still has so much over me 10+ years later.
PS. Some more music.
- Waver – Tadokoro Azusa – The title track of her self-produced album technically isn’t released until 2021/01/27 but it’s good!
- Hana no Ame – Ueda Reina – I am tickled pink by this art project. Or her earlier album.
- Wahl – Roselia – Nice album.
- Sky Full of Magic – Lapis Re:Light – Generally a lot of fun, all the songs. Wish it included the Sky songs though.
- Delicious Smile – Wataten 5 – Special image album from Wataten and it’s a great bright holiday spot in a dreary year.
PPS. I’m ready to put Database back on the list, but is NHK?