Thanks @mfalkvidd for your answer.
Let's see if I understood what you meant.
I could use an existing controller ( For instance Home assistance ), use MySensors Gateway ( without touching anything ) and link it to my arduino via RF24? I would like to avoid extending the gateway if it's not the way
But, how will the Home assistance know that I have a new Arduino with a RF24 module? The Controller will only talk to the gateway, correct? My arduino, in the other side, will have also the MySensors library and will implement the "presentation" method...but as far as I know, this communication is against the gateway.
So...the controller will be able to talk with this gateway and send commands to each sensor ( via gateway ) ? Is that the way?
I have the skills ( I hope at least )....but it's my first time that I will work with this kind of gateways, Controllers, etc...and as you can see, I'm a little bit lost about the responsibility of each component.
Again...thank you so much!