This article provides information when upgrading your Toolset version 10 to 11, you still see "Engineer's Toolset v10" within the License Manager.
This is not an issue. When Toolset version 11 is installed, if it detects a Toolset version 10 installation, it will uninstall it. Once it has been unsinstalled, the Toolset v11 installation begins. This process does not deactivate or replace the Toolset version 10 license, which means, it remains visible in the License Manager. This poses no negative impacts on your Toolset version 11 installation.