For instant clone pools, View Storage Accelerator is only needed for replica virtual machines. This is enabled automatically for individual pools and cannot be turned off on a pool level.
To complete View Storage Accelerator settings in VMware Horizon, configure View Storage Accelerator for desktop pools. See "Configure View Storage Accelerator for Desktop Pools" in the Setting Up Virtual Desktops in Horizon document.
To disable, you must disable View Storage Accelerator globally. See Enable View Storage Accelerator Globally in Horizon Console. However, this would also disable the feature for desktop pools that contain full virtual machines as well.
For desktop pools that contain full virtual machines, View Storage Accelerator is enabled for desktop pools by default. The feature can be disabled or enabled when you create or edit a pool. The best approach is to enable this feature when you first create a desktop pool. See "Configure View Storage Accelerator for Desktop Pools" in the Setting Up Virtual Desktops in Horizon document.