Alibaba sells its open video models as bilingual — on one of them, its own card recommends writing in Chinese

Every model card in Alibaba's open Wan 2.1 video family lists two languages, English and Chinese, and says nothing further about the difference between them. One card breaks the pattern. Beneath the download table of Wan2.1-FLF2V-14B-720P, the model that builds a shot between a fixed opening frame and a fixed closing frame, the maker writes that for first-last frame generation it trained the model primarily on Chinese text-video pairs and therefore recommends using a Chinese prompt for better results. The sentence is a single line in a note that otherwise discusses resolution, and it is the only place in the family's documentation where the two advertised languages are described as unequal. The four other builds of the generation - text-to-video at 1.3 and 14 billion parameters, and image-to-video at 480p and 720p - carry the same bilingual label with no such qualification. It matters because of what the model is for. First-last-frame generation is the closest thing the open field has to a storyboard tool: the user fixes both ends of a shot and the model invents the movement between them, which is also the only way to chain clips without each one drifting somewhere the next cannot pick up. That is the build an English-speaking studio would reach for first, and it is the build whose documentation says the English side of the training data was thinner. The usage figures suggest the model is admired more than it is run. It is downloaded around 1,800 times a month, a fraction of the plain image-to-video builds, while carrying 228 bookmarks - a high ratio of interest to traffic. Whether the language note is part of the reason is not something the download counter can answer. wujec.ai has added profiles for this model and for three other first-generation Wan builds the catalogue was missing: the 720p and 480p image-to-video models, published on 25 February 2025, and the small VACE 1.3B video editor from 13 May 2025. All four are Apache 2.0 by label, though the licence file the cards link to is present in two of the four repositories and absent from the other two.