Processed spliced and unspliced count matrices for existing scRNA-seq atlases Before I do this myself...

Is there any compiled batch-corrected dataset of the major scRNA-seq atlases (Mouse Cell Atlas, Mouse Organogenesis Atlas, Mouse Gastrulation Atlas, Tabula Muris, Tabula Muris Senis, etc.) with processed spliced AND unspliced count matrices?

I would be surprised if there is, but in the event there isn't, are there new pipelines in development that will make processing of raw data easier for studying RNA velocity?
I am not sure if there are preprocessed datasets available, however, Kallisto + Bustools was designed specifically for the rapid quantification of spliced and unspliced transcripts.