It is to be noted that the currency and the language of the invoices can't be changed for legacy Ahrefs subscriptions.
To get invoices in a different currency or a different language of the invoices you will need to stop the current subscription and start a new one.
For new Ahrefs subscriptions it is possible to change the language of the subsequent invoices.
To get assistance with setting up a new subscription with a different currency/language of the invoices, feel free to contact our support team via [email protected] or live chat.