To download the Satellite Imagery for ArcGIS Add-In:
Visit the product page at ArcGIS Marketplace here.
Sign into the Console and proceed through the on-screen prompts to download the Add-In:
Alternatively the Satellite Imagery for ArcGIS Add-In for ArcGIS Pro 3.0 and above can be directly downloaded here.
For technical assistance with the Add-In contact support@skywatch.com.