RTL (right-to-left) support was added since MinervaKB version 1.5.1. Since KB articles are very similar to regular posts, KB content always supported RTL, but many elements, like search, widgets, blocks icons need custom styles to work properly in RTL pages.
In order to use KB in RTL mode you need to switch to RTL (either in theme or in your language plugin). For example, if you use WPML and one of your languages is RTL, you don’t have to add any custom settings, the plugin will switch WordPress to RTL mode automatically.
Note, from technical point of view, RTL mode is enabled by adding appropriate dir tag on html tag of your document.
Once your site (or specific page) is in RTL mode, you don’t need to add any changes to MinervaKB settings, all appropriate stylesheets are loaded automatically.