let me please inform you that we have released ESET Endpoint Antivirus and Security for macOS 6.10.900
In this release, we're bringing following features compatible with macOS Big Sur:

• Firewall
• Device Control
• Apple M1 chip support

With that release, we're claiming full compatibility with macOS Big Sur.

Release details

Release date: 30 March 2021
Product: ESET Endpoint Antivirus/Security for Mac - 6.10.900.0
Type: Service release
Availability: Global excl. Japan

Release notes

• New: Firewall compatible with macOS Big Sur (11)
• New: Device Control compatible with macOS Big Sur (11)
• New: compatibility with Apple M1 chip (via Rosetta 2)
• Other bug fixes and minor optimizations

Known issues:

Device Control supports the following, due to macOS Big Sur SEXT limitations:

• Disk storage (HDD, USB flash drive) - all supported versions of macOS
• CD/DVD - all supported versions of macOS
• USB printer - not on Big Sur
• Imaging Device - not on Big Sur
• Serial port - not on Big Sur
• Network - not on Big Sur
• Portable Device - not on Big Sur

After applying firewall rule via management console for specific application running on macOS Big Sur, rule is mismatched and applied to all applications: https://techcenter.eset.nl/en/kb/articles/firewall-fails-in-eset-endpoint-security-for-mac-6-10-900-0-on-macos-big-sur