How do I change the search engine in the «Tor» mode of Brave Browser?

I know this question was done to death, but I’m still asking it anyway because I actually want to change it to http://searx3aolosaf3urwnhpynlhuokqsgz47si4pzz5hvb7uuzyjncl2tid.onion/search?q=%s …so now I’m asking…
How do I get a custom search engine for Brave «Tor»?