The schematic doesn't have any current path through the triac so it can't possibly work.
To make an AC capacitive dropper to drive an isolated DC-DC inverter to drive an AC switch seems like a complicated way to do it although with some modifications it might make it safe. I hope you can see why I was concerned about safety, the TTP223 module has a direct connection to the supply lines which in your original power supply was the incoming mains AC wires! The capacitive sensor pad could well have 220V AC on it.
I can't recommend any particular product but your best bet is to look for a 220V to 5V isolated power supply and use it's output directly to power the TTP223.
Brian.