My understanding is that for PAKE protocols such as OPAQUE (https://eprint.iacr.org/2018/163.pdf), the the adversary has no choice but to just do online attacks on the password. If this is true, I have 2 questions (which hopefully can be answered with references to RFC, NIST, etc.):
- What is a reasonable entropy level of the password so that is it practically immune to online dictionary attacks?
- What are good password requirements to enforce this minimum entropy level?