Yes, you can use Adguard with SOCKS5 on your S8.
There's actually two better solutions than that. (for Samsung phones only)
1. Disconnect Pro (You should find it on Galaxy store)
2. Adhell3 (Open source ad blocker)
Both this solution uses knox instead of vpn technology to block ads. So you're free to use any vpn along with them.
Disconnect Pro is not a dedicated ad blocker. It's a tracker blocker. But it blocks most ads anyway. It's a paid app though.
Adhell3 is a free and open sourced ad blocker + package and service disabler. It's really powerful but it takes some time to set up.
The dev doesn't provide an apk. So you'll have to compile it on your own or just use an apk from the mediafire folder that I'll link below. These apks are shared by a respected reddit user. So, you can trust him if you want.
Link:
MediaFire
But, just installing the apk won't work. You need to do certain things to make it work, prior to installation. You'll find all the instructions here:
Link 1:
Sign in · GitLab
Link 2:
r/Adhell
I know Adhell3 sounds complicated but it's not. It'll only take about 5 mins to set up if you use the apk from the mediafire folder.
And like I said before, you're free to use whatever VPN service you want to, along with Adhell3. Adhell3 doesn't use vpn technology to block ads.