In Epcot they sell passports with a bifold of pages & stickers for each country. If you go to the Kidcot stations & ask them to write you a message in their native language on their country's page, they will. And they'll stamp your passport too.
My husband and I have a tradition we started on our honeymoon where we asked for some message they wished to share with us. All the CMs were so excited to talk with us & write a wonderful message. They'd even translate it in English just underneath.
Each year we go on our anniversary and have another passport we get filled. I have a keepsake box I keep them in.
It's a wonderful souvenir that is personalized. Plus I think it's only $12 for the passport. Really reasonable for such a great memento. We've made some great CM connections doing this. Which is honestly one of the highlights of our trips. We love talking with CMs and finding out interesting stuff about their homes and Disney experiences.