Pretty much the title, but yeah I actually do use mods to switch between OSTs based on whatever I feel like playing.
A good example is when I’m playing a pre Bukhara (Persian Forgotten Battle) campaign chronologically such as Attila and Alaric (they might be the only ones), I find it most immersive to use the AOE1 ost.
Same deal for playing Romans in multiplayer.
I tend to use Age of Kings songs for the classic campaigns for nostalgia (the DE remastered soundtrack is really solace and bad in my opinion).
Naturally, I use The Conquerors songs for the Conquerors campaigns.
Also Conquerors fits Portuguese to a T in my opinion.
Depending on the timeline, I tend to alternate between AOE2 and AOE3 since AOE1 is no longer relevant.
I do genuinely think music makes gathering resources more fun, and I want to be fully immersed in the gameplay.
AOE3’s soundtrack is my favorite in the series, and it’s my go-to for multiplayer.
It also works very well for Babur and the Burmese campaign.