Finnish has a word for schadenfreude if you still want to use it, but be different.That used to be my favorite word but then it went too mainstream.
I like underground words. More clandestine words. Like surreptitious.
It's vahingonilo. Exactly the same as it's german counterpart. I'll leave it to you to find out how it is prounced. (Hint: Finnish is a phonetic language.)