There's some interesting info here, but the presentation is pretty poor. The worst languages are where the AI gets confused and loops keeps repeating the same text a bunch of time.
From the table on page 6 [1]
> Token explosion. The sentence repeated 45 times.
Figure 4/table 3 is pretty interesting. It shows that essentially all languages clustered at 0.1J/token, with a few outshots up to in some cases 4.8J/token.
They have 900 runs per language, so that's a pretty good sample size.