4.25.1 and here is the code behind that node:
void FNiagaraSystemInstance::SetEmitterEnable(FName EmitterName, bool bNewEnableState)
{
WaitForAsyncTickAndFinalize();
UE_LOG(LogNiagara, Warning, TEXT("SetEmitterEnable: Emitter \"%s\" is not currently implemented."), *EmitterName.ToString());
return;
}
Really wish there were less of this in the engine lol.
However, what works is making a user param float (set it to 0, or 1) and multiplying it with the spawn rate.