I think I just wouldn’t automatically pair [name_f]Margot[/name_f] + [name_m]Elio[/name_m] together they feel stylistically different. But aside from that I think they work together they feel artsy with a pan European feel. I also appreciate they shared the O sound which could trap you into a theme but you could embrace the theme by going for another brother [name_m]Hugo[/name_m], [name_u]Theo[/name_u], [name_u]Arlo[/name_u] and [name_m]Otto[/name_m] or for girls [name_u]Cleo[/name_u], [name_f]Oona[/name_f], [name_f]Ophelia[/name_f] or [name_f]Olympia[/name_f]. I think [name_m]Hugo[/name_m] + [name_f]Oona[/name_f] would be sweet.
I think they work well together!! It wouldn’t be my first thought for a sibling name, but as the previous poster pointed out they’re both fashionable, fairly pan-European choices that feel stylish together, not awkward!
I’m not a big fan of [name_f]Margot[/name_f] and [name_m]Elio[/name_m], just because of the different vibes of the two, but I would definitely go for [name_f]Margot[/name_f] and [name_m]Helio[/name_m]. The name is similar to [name_m]Elio[/name_m], but I think it just fits so much better.
[name_m]Elio[/name_m] and [name_f]Margot[/name_f] are beautiful taken singularly, but to me [name_m]Elio[/name_m] seems too ephemeral and soft next to [name_f]Margot[/name_f]. I think lots of suggestions other berries gave you are great, like [name_m]Helio[/name_m] (or Elios), Hugo…