I recently heard that being from the province of Hispania, the emperor Hadrian had an accent relative to the Romans from Italy which he consciously tried to overcome.

Would this accent have necessarily represented the first of the sound changes which are characteristic of Spanish? I know that the first evidence we have of romance languages as substantially different from Latin only comes from the 9th century, but on the other hand, it probably took on the order of centuries for any written attestation to catch up with they way people were actually speaking.

Do we have any specific evidence of various accents of Latin emerging in the 2nd or 3rd centuries, such as what they would have sounded like relative to Classical Latin? I would imagine that this evidence would be something like spelling mistakes in "proper Latin" or comedy making fun of people from various provinces.