I was wondering if the website Wookie Translator has any logic behind it or if it’s just a guy smashing his face against a keyboard.
We actually know several Wookiee words and phrases, courtesy of the Star Wars: Absolutely Everything You Need to Know factbook.
How to speak Shyriiwook
"WYAAAAAA!" = "Hello!"
"AARRR WGH GGWAH" = "Jump to hyperspace"
"ROOOARRGH UR ROO" = "I have a bad feeling about this"
"WWWAH RRROOOAAAH WHA?" = "Want to play some holo-chess?"
Wookietranslator.com does not provide a translation service that is consistent with these phrases, nor does it provide a consistent translation period (coming up with different answers each time for the same phrases).
The site is definitely not any sort of attempt at translation; writing the same word (“a”) twice got me different results both times.
According to this answer, Shyriiwook is a set of phrases made for Wookiees to say but not a real language.