To be fair 'space legs' can mean a lot of different things, and so can 'atmospheric landings'. Odyssey is providing something close to the minimum for each category for FDev to be able to tick that box if nothing else is added.
Hopefully there will be more to come after Odyssey of course, although how long it will take is anyone's guess
FDev did set some base lines for both back in the day. My read on EDO is that it’s aiming to fulfill on that 'stations Leg' brief, that it’s primarily a Legs DLC in terms of gameplay additions (FPS, NPCs in the flesh, stealth etc), with a side-order of Atmos.
We’ll need to see the full feature set to be sure. But wouldn’t be surprised if that’s what lands.
(If that is how it pans out, the plus sides might be fuller fledged Atmos & 'ship interior' DLCs down the line. If the game makes it that far )