As far as I am aware you cannot add Adguardhome easily to the router easily, sure it can probably be done, but I am not sure about space and cpu utilisation for it to run with everything else crammed on the router. I am aware diversion/unbound is another option but I don't want to cram more onto my already over loaded router (+ i like messing about with pi's)
The adblocking and safesearch that the clever people here seem to use is diversion and unbound with extras. I formerly used pi hole running off a raspberry pi, currently i use adguard on the same pi, as for me it is easier to configure the safe search than adding additonal scripts and code to pi hole, believe me I tried but I could not get safe search to work properly on pi-hole, wheras adblock it is so easy.
With adguard I point it to my ISP dns (so i get their family protection as well), in the router I have static ips, kid devices go to isp dns through adguard, everything else goes through quad 9.
Sorry this does not really answer your question but I am not that smart without doing a lot of research. I would assume theoretically being linux based it is possible however.