If you want to take it to the next level, Cloakist's Pro plan will let you do this for three sites, as well as:
Customise things like the document favicon
Remove any mention of Adobe Express in the page's tags, so when you share links on social media, your audience will see the link preview that you want them to see, instead of one that says 'See the story' by default
Alternatively you could do is set up a simple redirect from acme.com to express.adobe.com/page/LzZB6NejYSdaf.
That's a pretty good solution, used by many users of Adobe Express already.
If you're having any trouble figuring out how to set this up, simply google the name of your domain manager, e.g. GoDaddy or Namecheap, and 'redirect'. There should be an instruction page that shows you how you can set up the redirect so that you can start sharing acme.com.
The problem with this solution is that it doesn't keep the user at acme.com. They end up on the ugly Adobe Express URL, at which point they might find it strange that they were redirected in the browser.
That's why using Cloakist might be a better option for you.