The Roman poet Ennius gives the Roman equivalents (the Dii Consentes) as six male-female complements, preserving the place of Vesta (Greek Hestia), who played a crucial role in Roman religion as a state goddess maintained by the Vestals.

Based on this passage, who equated 12 roman gods with the 12 olympian gods/goddesses of the greek pantheon? Let's think fast. Stream of consciousness:
The relevant sentence in the passage is: The Roman poet Ennius gives the Roman equivalents (the Dii Consentes) as six male-female complements, preserving the place of Vesta (Greek Hestia), who played a crucial role in Roman religion as a state goddess maintained by the Vestals. So the final answer is The Roman poet Ennius.