My HA skills are less than my ISY and nodered skills so I am sure there is a more elegant way to do it in HA the what follows.
Just using HA you could create a binary sensor based on the scene. You could use a Template Switch - Home Assistant that reflects the status of the scene.
Then follow this to have a switch in lovelace that shows the status:
Would you be willing to buy a used ISY on ebay? The ISY natively out of the box presents scenes as switches in HA. Probably $100. If you have many insteon devices the ISY will blow you away compared to the insteon hub.
Are you able to run nodered? You could have a flow where the scene creates a switch entity. You could have that switch entity in lovelace. That switch would then toggle the automation (scene).
I’m lazy and would go the ISY route for all of its other benefits.