so people say that Nero is similar to Vergil (and for some reason that means that he is his son buuut thats not the topic here) now i say that Nero is waaayyyyyyyyyy more similar to Sparda than Vergil. Now let's check the parallels:
Nero and Vergil:
1) the desire for power, although their reasons are different. Vergil only feels like he needs it, past obtaining, he had no plans [evidenced by his lack of an answer when asked by Dante]. Nero's desire for power comes from a legitimate need, which is to protect Kyrie
2) Yamato. Although this is not as significant as most people seem to think, and I’ll explain later
3) Summoned Swords: they are shaped differently but Summoned Swords none the less
Nero and Sparda:
1) Sense of justice: strong sense of right and wrong and willing to protect the defenseless.
2) Rebellion: as a result of their sense of right and wrong they fought back against rebelled against their people. The demon army/world for Sparda, The Order of the Sword for Nero. they both also defeated the leaders of those they fought against, who in the final confrontation were giant, statue-esque enemies
3) Love: Sparda and Nero both fell in love with a human woman
4) Humanity: both having demon blood chose to side with humans and live their lives as such. they care for other people and are willing to put themselves at risk for the safety of others
5) Lone Wolf: Nero preferred to work alone and never asked for help, and despite having 2 apprentices, one of which he entrusted his "true power", Sparda fought against hell alone 6) this one is a bit of a stretch but, Energy: Sparda has energy blasts(least similar/important because energy blasts have been seen elsewhere. Drive, Nelo's fireball possibly), he can use energy to extend his swords length and form a spectral energy dragon, very similar to Nero's DT and DB
7) Yamato: the sword originally belonged to Sparda. It wasn't a manifestation of Vergil's power, therefore isn't tied to his essence/soul. i feel like his bond with/ability to fix Yamato is more of a sign of him being related to Sparda rather than connected strictly to Vergil. He also uses it more similar to how Sparda supposedly did, wielding just the blade rather than Vergil’s Iaido style. It also has a tendency to glow purple, as opposed to when Dante uses it
8) Necklace & Red Gem (bit of a stretch I suppose): both gave their lovers a necklace. Nero gave Kyrie a gold necklace with a gold charm of angel wings and a red gem on it. Sparda gave Eva the Perfect amulet, which has a red gem on either side.
if you have any for either side let me know in the comments and i might repost this with similarities to either side