WKWebView cannot use any of Safari extensions, unfortunately. I just use DNSCloak connecting to my private VPS instance to do adblocking over DNS which kinda works fine, but leaves out a lot of blank canvas in the page.
Biggest drawback is that DNS based content blocking has no way to apply cosmetic filters.
Ads on platforms that deliver their ads embedded and from their first party domains (think google, facebook, reddit, youtube, instagram, linkedin, amazon, etc.) can not be blocked this way.
The only two places I see ads on my phone (currently using NextDNS, earlier DNSCloak) are Amazon sponsored listings inside the Amazon app, and Twitter sponsored content in Firefox.
