First thing that came to mind is the 2nd opening of Darker than black, Kakusei heroism by An Cafe ( honestly still a banger, I don’t care what anyone says )
Let’s go old-school: BUCK-TICK’s Gessekai was used as the opening for the series Nightwalker: The Midnight Detective in 1998.
Their song Dress was also featured as the opening theme for the Trinity Blood series in 2005, in an updated “trinity blood mix” (couldn’t find the actual opening video on YT).
Only a year later, their song Kagerou was the 2nd ending theme for xxxHolic (season 1).
And in 2010, two of their songs were featured in Shiki: Kuchizuke as the series’ 1st opening and Gekka reijin as its 2nd ending theme.
I’m sorry but that’s incorrect. The year was the same, but ABS recorded their cover version specifically for B-T’s tribute album (without any anime tie-in). It’s a mighty fine version, that’s for sure tho!
Mandela Effect because I literally remember watching this show (from the first episode till the end) and seeing it say Dress and it mentioning Abingdon Boys School and Takanori Nishikawa in the credits.