Such a weird mishmash of German, Latin and Greek, although Felix is extremely common in Germany too. Sigurd isn't though, that's some old germanic kinda name, like Æthelwulf in the anglosphere.
If someone in central Europe named their kid that way, that would be a give-away for a nationalistic/conservative ideology. Though Atreides obviously is from Dune lol
Funnily enough, I was talking with my kid yesterday how my parents almost named me Levi and was joking how I could just force people to call me Leviathan instead.