I met my friend who is more fluent in Japanese than I am over the winter break and discovered that on some machines you CAN change your English name for the label stamps!
On the graffiti screen outside, some machines ask you to add your names so you can make personalised stamps. Flicking through recent puri I can see this on: Me Her Jyoshi, Mero Mero, Milk Beauty, Essence and BF Manual. On some of them you can only enter your name in Japanese script, however it also has romaji (alphabet) stamps. So if your names doesn’t transcibe perfectly you are left with a mangled version, or having to use a nickname. I thought this was all the machines but I was wrong! A few of them let you edit the romaji to a different spelling.
Here’s Me Her Jyoshi for example:
At first there’s nothing to show you can do it which is why I may not have noticed (my excuse!)
Once you type something in, however a button pops up next to the romaji saying “Correct the romaji”
If you click that, then you can edit the romaji using the alphabet and type in your correct name (or anything you want!)
My friend changed hers because if she left it as it was it would end up being ‘Kyasarin’ which looks weird. I decided to stick with Samancha because it’s my nickname anyway.
Example pic at the top of the post and one more for luck:
Here’s the screen on Milk Beauty:
I took this picture way before I realised you could change things but I think the same button pops up next to the romaji version.
These are the only two I know for sure, as I check others I’ll put them up on my twitter.
Hope this helps!