Please listen to that special french [ə] : “Je”. It’s quite close to the open [œ] “peur” when sung. Of course it can be closed like an [ø] when spoken, like “deux”, but preferably not in an opera which requires formal language. In fact it’s between [ø] and [œ] : if one must choose, definitely prefer the latter ! You are welcome to vote for the next aria ! ✍