I used to work with someone who had a message telling people she only checked her email twice a day. You pretty much needed to call her if you needed anything outside of those times. (She worked in a remote office.) I think she had read one of those books on efficiency that recommended scheduled email time. But there were problems with this: 4. My department often had to email attachments or text to illustrate our questions/concerns. And we were on deadlines. Reading a page of text over the phone was not an efficient use of anyone’s time 5. She did outreach & was often out of the office on site visits, trainings, or travel to these places, but never ever set her OOO for these, because she was “working.” However, she was effectively not available to read emails from other staff until after hours on those days.
It got bad enough that others began begging someone to cull the list. Reply all, of course (thankfully it didn’t turn into an explosion of replies all). Someone finally did remove the email from the list.

If your email client allows it, you could always just use an image to express your out-office sentiment, like this one. After all, they say that a picture is worth a thousand words — and visual content is still essential to successful marketing.
Get the time and date right for when the automatic emails start - you could choose the the moment that you actually leave the office, or some cheeky people choose an hour or two before they leave, saying that they are busy handing over or wrapping up to deal with customers or other colleagues. They are still able to check the emails they do get anyway, to reply properly to if they want to.