How do I correctly format a featured artist in Local Files?

[musichooley]

I'm currently trying to put Aphex Twin's Warehouse Project DJ set onto Spotify through local files, and I have split the long recording into the tracks that are performed.

Due to it being a DJ set, I want the artist field for songs that aren't Aphex Twin's to be formatted like ("Aphex Twin, Steinvord"), as it appears in playlists throughout Spotify.

I've worked out the correct way to format this in Windows, which is to format it like ("Aphex Twin/Steinvord"), however in Spotify, it appears exactly like that in plain text, including the slash.

My question being: is there a way to format multiple artists for Local Files? I assume it will involve changing the metadata in Windows, but I've not managed to find out how it's 'correctly' done.