I personally wouldn't enjoy it that much as a fallout game, the idea of say going through post nuclear version of Tokyo or some place like that sounds awesome to me it would likely screw with lore and a bunch of things that make fallout fallout would be gone. Like the vaults since they were only in the U.S. if my memory serves me right. It would be a fun game but lack a lot of the fallout nostalgia and familiarity i enjoy.
A game without the brotherhood, vaults and likely super mutants would not feel much like fallout.
A game without the brotherhood, vaults and likely super mutants would not feel much like fallout.