Fervor of Battle DOES NOT Stack with Abilities

Hey guys, I just hopped into a game to test out how does fervor stacking work on ekko and Illaoi, and i found that ekko's q didn't give any fervor stack, nor did Illaoi's q. Also you should be able to stack fervor on the enemy spirit, as i assume it works just like the rest of the keystone and you can proc TLD and GOTU as well as DFT. If im correct it is supposed to be stacking every two seconds for abilities, but it does not. Feel free to test it.

Cheers.