As the title says! My choice, for now, is Leta, directly from Mullvad. I really like because there are no ads by deafult, which is particular important since those ads usually lead to malware.

Otherwise, i like mojeek (same reason).

They both have a strong privacy policy and search results are good enough for me.

Leta: https://leta.mullvad.net/faq

Mojeek: https://www.mojeek.com/about/privacy :)