I read that the Adguard English filter is originally based on the Easylist filter. Does this mean that these two filters are (for the largest part) overlapping?
I now have both filters enabled, but maybe that isn’t necessary.
Basically the English filter = AdGuard base filters + EasyList. So yes, the English filter is indeed based on EasyList (and does merge the newest, up-to-date changes with upstream EasyList). So yes, you don't need both enabled at the same time due to the overlap which will save you greatly when using AdGuard for iOS and dealing with the Apple Safari content blocking limit.