Is that normal, when someone suicide in first, the ennemy lost his turn ?

Like if a talonflame with 1hp, use brave bird, and die, but the ennemy's pokemon still alive, we can't attack, even if this attack isn't offensive like stealth rock ?

i know what you mean, similarly if an opponent switches out as i attack, then the poke they switched in died to stealth rock / spikes and i didn't even attack yet, then my attack is nulled and i don't have an extra hit on my opponent that switches out.

 

i can't recall if this is intended or in the regular pokemon games

if your attack isn't offensive you should attack... on pokemon showdown is it..

it's just another bug xD.. yes, u should be able to use attacks. That's how it is in pokemon games...