Listen, this is a very specific topic to be iffy about, but for your knowledge, the Roman gods are not the Greek gods.
The Romans were big on syncretism (the combination of different forms of belief or intellectual thought) and the adoption of foreign gods. The Greek deities were known since very early periods via the Etruscan culture, which was heavily influenced by Greece since the middle of the 8th century BC because of trade routes as well as the Greek cultural potential and would come to be completely engulfed around the third century BC with the Roman-Etruscan wars, but just like you’d see the Romans claiming the Germanic tribes worshipped their own gods under different names (the Germania by Roman historian Tacitus, written around 98 AD), the same happened here, and the fusion wasn’t 100% accurate.
While in the case of Zeus and Jupiter, for example, it worked well, Venus is far more motherly and political than Aphrodite (as Mars is the Father of Rome via the myth of Romulus and Remus, Venus is Venus Genetrix, Venus the Mother, and the only time you’ll see Aphrodite being motherly is in… the Aeneid, a distinctively Roman piece), Mars is an agricultural god as well as the god of war and has way more political connotations than Ares (he was a member of the archaic Capitoline Triad), Mercury is far more linked with commerce than the more pastoral Hermes, and the list goes on. Apollo was imported directly and very early (a temple for him, the Temple of Apollo Sosianus, was erected in the city of Rome as early as 431 BC), thus keeping the name but undergoing a very distinct Romanization of his attributes and worship. Janus, Quirinus and Terminus were very important Roman gods which had no Greek equivalent.
Isis, for example, was worshipped as herself, equated with a number of deities in both the Greek and the Roman worlds and some of her methods of worship and symbolism were associated with the Virgin Mary. It’s a far more complicated scenario, babes, especially when you consider Alexander’s conquests and the expansion of Hellenistic culture as well as its contact with many other cultures.
Syncretism is way more complicated than “the Romans just stole the Greek gods and gave them different names, the uncreative fucks”. The traditional date for Rome’s foundation is 753 BC and the Western Roman Empire would last until 436 AD. That’s over a thousand years of conquest, trade and growing and shrinking territories, and none of these factors are likely to leave a religion unaltered.
Besides, the practice of religious syncretism is way older and more common than you’d expect. The Akkadians did it to Summerian deities a few thousand years before this especially after the conquest of Sargon of Akkad in 2340 BC (“Mesopotamia: the Sumerians”. Washington State University). The Greeks were doing much the same with the Roman pantheon itself (Dionysus of Halicarnassus and Plutarch use Greek names for Roman cult), with the Egyptian pantheon and with the Scythian pantheon (Herodotus in both cases, though the associations would outlive him, such as the case of Zeus/Amon).
So, no the Roman gods aren’t the plagiarized versions of the Greek gods, and I could defend this in front of a jury.
While I agree with the claim that the Roman and Greek gods are not the same, I'd like to point out that my Classics prof in uni would vehemently disagree with you on why they are so similar.
As she put it on the first day of Classics 101, "The Romans did NOT borrow from the Greeks. The reason their gods are so similar is that the two cultures had the same parent culture, and their religions used to be the same, not unlike the Norse-Germanic religions or Abrahamic religions."
That being said, the Romans did indeed love adopting other religions' deities. The same professor also talked about how one of the first questions the Romans would ask a new culture they met was "Do you have any gods, and if so what are they" so they could add a statue of said god(s) to the Parthenon.
