https://www.cambridgeclarion.org/50.html
No bots detected for Brave.
> Neeva
Is listed but I'm thinking their own index is very small.
>Infotiger
This is one to watch long term. Still only a small index and the results are not really usable but they seem to be determined to build both English and German lang. indexes. Might have legs.
>Marginalia
Lovely little engine that isn't really trying to compete as a "General Web Search Engine". Marginalia favors text heavy websites so it's going for blogs, old fashioned forums, static HTML type sites. It is not interested in anything too commercial, too ad heavy, too image heavy, kinda the opposite of the current Google.
>index is very small.
https://radar.cloudflare.com/verified-bots is pretty good for identifying well-known bots. Neeva seems quite active (seen them in logs from Amazon ranges) - who knows if they're indexing all they see though.
>Brave
Indeed. Surprised not to hear more about this.