It is true that QRNN had results on mostly small-scale benchmarks, but it seemed that Bytenet especially the second version had SOTA results both for language models with characters and for machine translation with characters on the same large-scale En-De WMT task that is used in this paper.
MT with characters, with regards to ordering, structure, etc, is potentially much harder than with words or word-pieces, since the encoded sequences are 5 or 6 times longer on average, and the meanings of words need to be built up from individual characters.