Any ferries from Palermo, Sicily to Valletta, Malta in May?
Timetables?
No, the only ferries between Valetta and Siciliy are from the southern tip of Sicily in Pozzallo (http://www.virtuferries.com). Consider a short flight instead.
Ferries to Malta from Sicily are south of Siracusa.
I considered ferrying from Sicily to Malta back in 2015 and was surprised at how costly the fares were, given the comparatively short distance. I'd definitely look into flying.