No. At most futures that happened to get dispatched to the same worker might have access to the same workspace.
I do not know the extent to which two futures on the same worker might be able to share objects; plausibly they might be able to use assignin('base') or per-worker "global" to access the same memory.
If you have two futures that might have been assigned to different workers, then you have to pull the values from the first future into the main thread before dispatching to the other future.
