Would this happen to help?
Safari and WebKit
New Features
Support for Web Extensions is now available. Existing Chrome and Firefox extensions can be converted for Safari using xcrun safari-web-extension-converter and distributed through the App Store for use in Safari 14. (55707949)
Webpage Translation is now available in the U.S. and Canada. Supported languages include English, Spanish, Simplified Chinese, French, German, Russian, and Brazilian Portuguese. Safari will automatically detect if translation is available based on your Preferred Languages list. (64437861)
Source: https://developer.apple.com/documentation/macos-release-notes/macos-big-sur-11-beta-release-notes#Updates-in-macOS-Big-Sur-11-Beta-3