Could the closest approach of stable orbits of two earth sized planets allow life to jump between? How close could two earth sized celestial bodies get in their nearest approach either as planets or moons around a larger planet?

Close enough for atmospheric interaction in a stable orbit at nearest approach, or for non-space-fairing species to somehow make the jump without cosmological assistance (aka asteroid impact)?

It seems just from using the roche limit of an earth to earth sized bodies any approach under ~20,000 km would be unstable in the long term, which is orders of magnitude beyond a normal atmosphere size.
From comments

no, you can't have orbits anything like that close. Nor can you have a large moon anything like as close as you are thinking. 2 earth sized planets near each other's Roche limits would cause catastrophic earthquakes. Independent orbits would need, probably a few million miles apart for stability. Orbiting each other you could work them to perhaps, earth-Moon distance or even closer assuming they were tidally locked to each other to avoid too much disruptive tidal forces.

BUT if this is for a story: don't forget the other direction. One could say it is perhaps generally agreed today that "panspermia" can happen: life - microbes - via asteroids/etc can travel large astronomical distances. If we learned today that Mars has life - and indeed it's the "same" as Earth life - we'd assume that it travelled via ejecta - the Mars-Earth distance is no problem for such a putative story



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