Does the khulʿ take effect if the husband has not received the money transferred to him by the wife, knowing that she has fulfilled her obligations and more, and that she warned the husband about the difficulty of transferring to the account he insisted upon?

If you seek Khul' (divorce at the wife's instance) from your husband in exchange for a compensation ( عوض ) and he accepts it, the Khul' is valid, and the Mahr becomes a debt upon you. The Khul' is not invalidated if the Mahr does not reach him. If you pay the Mahr to the bank account specified by the husband, you are absolved of your obligation, whether he receives it or not. However, if the money does not reach the bank account designated by the husband, your obligation is not discharged, and you may seek recourse against the entity that performed the transfer.