I actually think the category originally chosen by OP was appropriate:
Brave Search (Beta)/Search Feedback
This topic is a duplicate topic in the Brave Features Requests category, and Brave discourages duplicate posts in this category.
About the Brave Feature Requests category
Search for Duplicates
Given the amount of reports/request we get each day, there’s a good chance that someone else may have raised the issue with us already or may have been resolved. Before posting, use the search bar on the top-right corner of the website to see if other users have raised the same concern.
A quick search found 3 topics for iOS and 1 for Android already created in the Brave Feature Requests category for this feature.
Address bar on bottom would be amazing
There are also open Brave GitHub issue reports although none have been triaged:
Tab bar and search bar at the bottom please #20923
[Android] Sticky URL/Bottom Bar #11337
Moving this to the general browser feedback category as this is a duplicate request (multiple times over) in the Brave Feature Requests category.
@Raye you can also post (and vote!) on any of the above feature request topics already created. A post in the Feedback category is also a good way to indicate to the development team that there is still interest in this feature. Take care. 