https://www.onesearch.com/ - aimed at privacy & encryption - operated by Yahoo and most likely using Bing as the back end, as Yahoo signed a deal with Microsoft.
https://www.ecosia.org/ - aimed at offsetting the energy used for searching by planting trees, based in Germany - results from Bing, Yahoo! & Wikipedia
https://www.ekoru.org/ - another Eco conscious search engine, this time profits go to cleaning up the oceans. Based in Malaysia. Not sure of back end technologies, but looks Googley from their results
https://www.qwant.com/ - A French search engine with privacy & sustainability in mind. Originally used Bing as the back end but now they're not telling, but they keep signing Microsoft deals so likely to be Bing + their own algorithms.
There is a fifth within the browser, Gibiru, but they have no information about who they are on their website so I've not linked to it.