deeply nested triples or blank nodes?

[valecarriero]

deeply nested triples or blank nodes?

[TallTed]

Note that RDF-star (which was initially written up as RDF*, but that name is very problematic, and has been set aside) is far from finalized, so everything you're working with should be considered experimental, at best. Along these lines, note that OWLStar was last changed in February 2021, more than a year before the final report was issued by the RDF-star focus group of the RDF-DEV Community Group.

According to current RDF-star draft spec, you can nest triples, as in your first example. The :isSemantic visualizer appears to need some updates, given that it chokes on that example data. (I also note that they refer to both RDF* and RDF-star, treating these names as synonyms, but as I noted above, that is not the case.)

I do not think you will need to take the "blank node" route you describe — but that depends on the tools you use accepting the nested route.

[valecarriero]

Thank you so much for your useful feedback, @TallTed!
Valentina