Yes, we know its impossible. It's alternate history. Let's try not to be pricks.
I suppose that this should be in Alien Space Bats, prefaced with something like "Suppose Alien Space Bats came along and arranged for humans to evolve in Pangea, using time travel or time information sifting to arrange that the humans evolved to be what we are now or as close as you could get with the mammal like reptile stock available."
My thoughts:
Agriculture is probably slower starting off, definitely a different repertoire of domesticated plants. No fruits or flowering plants during this period. No grasses or grains. So probably roots, tubers, leaves etc., adjusted for edibility.
I'm not sure if trees or hard woods have evolved by this time. Probably not. So there may be issues for tool making, construction, and firewood fuel.
I suspect a very long and protracted hunter gatherer stage, lots and lots of populations moving back. Very likely little racial differentiation. Humanity is mostly black or brown, with ethnic groups here and there and lots of intermediates, but no real races. Extinction of just about all the megafauna eventually. Surviving animals will be very fast breeding.
Agriculture when it hits will spread quickly. As will copper, iron and bronze, either through trading networks or simple spread of the technology.
However, humans will peek out. Reason - lack of fossil fuels, lack of oil and coal. No industrial revolution per se.
The steam engine etc. may evolve, and may even become widespread, but for the most part, it'll be a specialized toy. But the timeline for that sort of thing will be slower and it'll aways be small scale. The sorts of mass production that were a hallmark of the industrial age, unlikely.
No likely domesticated animals - unless ASB's evolve horses and cattle along with humans, or unless there are local species that can be adapted. Unlikely.
So no great Mongol type empires, no cavalry, no chariot warfare, no beast-assisted agriculture, etc. etc.
Empires and states will be dictated by foot traffic and social organization.