There's a website called Run Repeat that bills itself as "#1 Sports Shoe Review Site". It does meta analyses of shoe reviews.
In the search rankings-of-wide-hiking-boots is a list of high ranking models of hiking boots that are available in standard and wide widths. It is "based on reviews from 195 experts and 9,986 users" (as of Oct 2018). The brands that appear in the top 20 models are as follows:
If you search for hiking shoes or sandals on the same site, these brands appear on the top 12 models list:
Note that when asking for wide-fitting boots/shoes in a store (or on an outdoors advice site) one often hears comments such as "brand_x tends to have wider models". While some of those brands may have boots that exist in wider versions you will often find that only the standard widths are actually available and that, while they may be slightly wider than average, the offerings are simply not wide enough for those of us who have wide feet.
If you have very difficult-to-fit feet, and can afford it, you have the option to get custom-made boots.
The first two offer hand-made leather boots while Tecnica offers customizable liners (like some ski boot brands).