When we search something, your plugin edit current URL to add his queryparams (https://prnt.sc/vg5un7). They aren’t considered SEO friendfly, because you can see the parameter (?s=). It’s possible to work with clean URL, transformin this parameter like “http://qgallery.smartbrand.es/aston+martin” or something similar.
Well, that does not really do anything, as those “pages” are not indexed, google or other search engines does not do a search action when indexing the pages.
You can change the override method to “POST”, that will send the parameters via post mehtod and carry with cookies. It is visually more pleasing for sure, but it does not affect the SEO whatsoever