I'd go to LinkedIn (or their About page if they are small enough) and just look at the people. The more diversity you see, the more they are walking the walk. You can also look thru past employees via LinkedIn (might require premium account) and reach out to diverse folks who've left the companies you're considering.
Funny thing about the beer-- we got draft cold brew coffee at work and went out of our way to design and laser-cut a tap handle that says "Coffee" so candidates wouldn't think it was a beer keg.
Side note: I find it funny that 9/10 of Textio's software engineers are men, but they do have two "customer success engineers" who are both women. No women in senior technical roles.
Funny thing about the beer-- we got draft cold brew coffee at work and went out of our way to design and laser-cut a tap handle that says "Coffee" so candidates wouldn't think it was a beer keg.
Other ideas: run their job post through Textio (https://textio.com/ ).
Disclaimer: I am a white dude, but my company of 65 (in Seattle) is about half women on the engineering side of things. It was a lot of work.