No. Blog Sites on the same subscription share one AI credit balance. A Blog Site is a separate blog website, not an individual article or a language version. If your plan lets you run three Blog Sites, it does not give you three copies of its credit allowance.
If one Blog Site uses credits for a draft, the shared account balance drops by that amount. Pricing also shows an estimate of how many standard AI posts the credits could generate. Posts kept is a separate limit on stored original articles across the account. Renewing credits does not reset that count.
See current Blog Site and credit allowances or the guide to plans and credits.