1Blocker lets you block ads, trackers, and other unwanted web content. It's easy to use and doesn’t slow down Safari. 1Blocker comes with over 120,000 built-in blocker rules. It is very configurable and all your settings are synced over iCloud.
I don’t have much experience with adguard but have been using 1blocker for years and have been happy with it. It’s of course not system wide ad blocking (it won’t block YouTube ads for example) but it works great in safari.