It must vary from subject to subject, teacher to teacher and school to school.
For example, lots of teachers (me) don't make long ppts to deliver a lesson. If you normally have a short slide on the board, some handouts and lots of discussion, then you've got to make one. All new format too, to show remote learning expectations on every slide.
Or you need to narrate over your ppt or make a video from scratch and upload it (takes forever if WiFi bad - I took 1.5 hrs to upload one lesson the other day).
Or you've changed the order of your syllabus as a topic just doesn't suit remote teaching at all (drama/art/tech) so are planning from scratch.
Or your school insists on loads of admin tasks around each lesson (download register, upload register, contact non-attenders, download recording of your live lesson, change permissions, email to students).
Your workload for each lesson sounds bad enough!