My reading of the period is that the Franks (and Goths, for that matter) would not differ significantly in terms of military equipment from the Romans in the mid-5th century. There might be some differences in terms of hairstyles or textile/shield decoration, but I think the new Victrix late Roman sets are the best way to go for Franks. Wargame Atlantic does have a set of Franks in the pipeline, but from what they’ve shown so far it leans more into the stereotypical barbarian look, with fur vests and that sort of thing.