An analysis of personnel is an incomplete and non-definitive answer but ought to be a useful starting point.
Paradigm Academy does not list its team on its website. However, a quick search on Linkedin yields 16 results (13 with public profiles) for people at Paradigm Academy. Of these 13 profiles, 7 include experience at Leverage Research or allied organizations, and a further 4 are well-known to have worked for Leverage Research. Edit: at the request of Julia Wise, I've encoded the names in rot13, so that this comment doesn't broadcast their association to LR to everyone who Googles their names.
Leverage Research, Paradigm Academy and Reserve:
Zvpunry Phemv
Leverage Research and Paradigm Academy
Rzvyl Pebggrnh, Wrna Sna [YE abg pvgrq], Nabalzbhf Crefba [YE abg pvgrq; cersref abg gb or nffbpvngrq jvgu YE]
Paradigm Academy and Reserve:
Xriva J, Urael Svfure, Qnavry Pbyfba
Paradigm Academy only:
Nynaan Xebjvnx, Wnaryyr Jvyyvnzf, Wbanguna Jnyyvf [Frrzrq irel vaibyirq va YE], Zvaql ZpGrvthr [Frrzrq irel vaibyirq va YE]
Paradigm Academy and Bismarck Analysis:
Mnpx Yrenatvf, Oevna Oheaf
Edit, June 2022: I should hope it goes without saying, but please don't harass these folks for having worked at LR.
My impression is that Paradigm is a spin off from Leverage Research. Where Leverage functions as a think tank for producing research, Paradigm is a training organization, which draws somewhat from Leverage’s research. They seem to have separate staff, though as you say, staff often seem to move between them. You might expect people to move from one to the other if you think it’s a good idea for someone to do some research which then prepares them for teaching that research. Having organisations branching off from each other when some members want to pursue some new mission seems relatively common – to take an example I know about (because I was involved in it), the initial researchers at the Global Priorities Institute were all employees of FHI until GPI split off from FHI.
Hopefully this will be clearer when Leverage launches a website of its own.