Not sure if this qualifies as online for you, but I have an insurance company do the compulsory insurance and tax sticker for me at cost. I send a scan of the Blue Book and transfer slip using Line, and get the documents in the mail in less than 3 days
I submitted the first phase at 11am. It took 15 minutes to be approved. I submitted the second phase by 12pm and the COE email arrived at 2pm. 3 hours in total on a Friday afternoon