The official Homeseer driver channel information is here.
sign up for the channel, using the link in the post above.
install the driver or drivers for the devices you have to your hub within that sign up process.
once installed, then go back to your ST app and on a device tile, use the 3 dot menu “Driver” option, then Change Driver. You should be given a list of drivers installed on your hub, which now includes the Homeseer drivers you installed earlier.