In macOS Big Sur (macOS 11), kernel extensions in the current form will no longer be supported and will be replaced by system extensions.
MacOS 10.15.4 and later will display Legacy System Extensions dialog to inform users about upcoming changes.
Click OK to dismiss the notification. Currently, no action is needed. Your ESET product will continue to work unaffected.
ESET will release a new version (v6.10 )of products for Mac with the full support of macOS Big Sur before the release of macOS Big Sur.