Fennec (Firefox based), with Ghostery and uBlock origin installed.

You'll have to set add-ons up as a private collection for them to work, but it's easy as pie.

I think you might try to bite off more than you can chew here. You keep insisting that you want to somehow see the data that's saved on your device. Why exactly do you want to inspect the local cache of those sites? What do you expect the benefit to be? And what's more: what do you expect such a local cache to look like?

I use Firefox focus for random browsing, normal Firefox for general browsing that I want to keep the history of, and Mull for anything where I want to absolutely minimize tracking / enhance privacy.

I use Iceraven with ublock, privacy badger, decentraleyes and canvasblocker.

https://www.privacyguides.org/en/mobile-browsers/

https://divestos.org/pages/browsers

Not a complete answer, but I stand behind Privacy Browser. The dev has a great blog explaining how the browser works:

https://www.stoutner.com/webview/

https://www.stoutner.com/privacy-browser-android/core-privacy-principles/

https://www.stoutner.com/privacy-browser-android/permissions/

I appreciate the transparency of the Dev and I am looking forward to the long-teased 4.x series that will ship with its own webview.

If you decide not to use it, keep it on your watchlist.

I would say go with either chromite or firefox. Both are private, supported for now, and can block ads (UBO on firefox)