I am German and it's not pronounced with four syllables.It is either ee-zah-BELL or EE-zah-bell (both pronunciations are possible).Yes, in German we usually pronounce every letter, but Isabelle is seen as a French name and pronounced with three syllables.
― Anonymous User 9/3/2021
2
In French Isabelle is pronounced very differently than in English. Isabelle Ee-ssah-bell I- in French is pronounced like a long e S- pronounced with sibilantly. NOT like a z in English.
The English pronunciation of this name is very similar to the French, only the French (and Germans) place the accent the second syllible, so it's is-AH-belle, while in English it's is-a-BELLE.