So basically the title is not completely true. The problem is I would like to stream Youtube on the tv from my phone without using the remote to start the tv. But chromecast isnt even shown when the tv is off. Is there a way that I can do it like with my normal chromecast where it starts up the tv?
If your TV supports Standby/Sleep mode, that should do it.
Or else, if your TV has CEC functionality, connect the Chromecast power to a separate power outlet instead of drawing power from TV. This should give the casting option on your phone and the CEC will help in starting the TV with the cast command.