Astro Mosaic can be configured to show your own lens. You can either add it to the list of existing services or just replace them all with your own.
Here is an example how to add my own camera Fov:
https://ruuth.xyz/AstroMosaic.html?add_service=Fuji%20X-T3,400mm,206,137,60.04298,24.24452
You can find the new service in the Service drop down.
URL parameters and other options are listed here:
https://ruuth.xyz/AstroMosaicConfigurationInfo.html
That page has links where you can convert camera+lens combination into arcminutes that is needed by Astro Mosaic.