These are top and recommended layered navigation extension for Magento 2.

1) Landofcoder layered navigation extensions

Are you looking for a fast, user-friendly navigation system which can allow your customers to browse your product catalog comfortably and impressively? Then, our new Magento 2 Ajax Layered Navigation Extension can satisfy you at the very first sight with its multiple filters, ajax load and user-friendly interface.

Link: https://landofcoder.com/magento-2-layered-navigation.html

2) Mageplaza layered navigation extensions

Magento 2 Improved Layered Navigation brings a list of filters to help your customers search and get the favorite products in the shortest way.

Link: https://www.mageplaza.com/magento-2-layered-navigation-extension/

3) Mconnect layered navigation extensions

Present your customers with memorable shopping experience by adding an improved layered
navigation to your Magento 2 store.
Magento 2 layered navigation multi select lets your customers search for the desired product quickly
through AJAX filters. Supports configurable products!

Link: https://www.mconnectmedia.com/alnavigation-magento-2.html

4) Amasty layered navigation extensions

Magento 2 layered navigation multiple select equips your store with a user-friendly navigation system to let customers browse your product catalog in the most comfortable way. Use multiple fully customizable filters and handy widgets.

Link: https://amasty.com/improved-layered-navigation-for-magento-2.html

I suggest one more extension to this list: Mirasvit Layered Navigation for Magento 2 https://mirasvit.com/magento-2-extensions/layered-navigation.html. It contains all key features + Improved Sorting, Infinity Scroll and Shop by Brand functionality.