So just thought I would update this with the solution I came to in the end (hate when other people ask the question you want answered and then never follow up)
I bought a zigbee2mqtt usb dongle from eBay, I believe it’s a CC2511 or something similar
I set up zigbee2mqtt in a docker container with a mqtt broker in another container, not sure why I didn’t use the mqtt in home assistant but thought I needed it to be separate.
I bought a Xiaomi double rocker switch, it’s battery powered, has to buttons that can do many different clicks.
I now have that switch set up in home assistant to toggle a sonoff mini that is connected to an outside light on the left click and toggle my garden lights on the right click.
Works perfectly
Thanks for everyone’s help