What are the characteristics of Labelese?

[Koen G]

How can different source words be mapped into homographs and still produce a high TTR?

You make a good point. If the VM is encoded in any way that generates homographs, we'd expect a relatively low TTR. Unless perhaps we assume that it started at a top-tier TTR in the first place, like classical Latin or even something like Sanskrit. Or one of the many possible candidates I haven't tested yet. (I'm not saying this is likely the case, but maybe theoretically possible?)

Now about the labels specifically, there is nothing wrong with apparent homonyms on the one hand and high TTR on the other. You know that high TTR is influenced by inflection, conjugation and other grammatical processes which change the appearance of a word. But in labels we might expect words to mostly appear in their base forms (exceptions exist, like the labels with Rotae Fortunae I've posted before). If we can assume a set of labels to be dominated by base forms, like nominative singular and plural which most languages have, then TTR-increasing factors are mostly absent.