Light button that sends Json commands to an espeasy flashed sonoff

Hi,
I am just migrating from domoticz to Home Assistant and have a small problem with a couple of flashed sonoff devices.

In Domoticz I could just specify a url to be called on a button push and thereby send json commands to the sonoffs.

In Home Assistant i thought, that a command line button would work, but i does not take the url as an on or off command.

for example

switch:

Can someone help to get this working?
I specifically want to use the json commands and not mqtt.

Thanks in advance.

I think u need a RESTful Command

Or an RESTful Switch