There isn’t an out‑of‑the‑box way to do this. Chromium’s build system is designed around producing a full APK (or AAB) for Chrome. Simply switching the target type (from android_apk to android_library) won’t work because many internal GN files (like rules.gni and internal_rules.gni) and other dependencies assume an APK build. In short, converting Chromium to output an AAR would require extensive, non‑trivial modifications across the build configuration and codebase.

As an alternative, consider the officially supported integration methods (such as using WebView or Chrome Custom Tabs) if you need browser functionality in your app.