Blockada is most likely a DNS level blocker, netguard supports that. Alternatively you can configure it to point the DNS servers at NextDNS if you just want a nice UI to configure block lists (though NextDNS might track you).
NextDNS as a manual DNS server on Android is the adblocking solution I've been using for years. Is there any reason to believe they would track you, any more than any other DNS provider?