Merge changes from one repo to another with different tree structures

Question

I have two Git repos, foo/master and bar/master:

In foo:

code_root
->dirA
  ->dirB
    -> *some files*

In bar:

Answer 1

So, you are saying the files are essentially the same in both in foo & bar, just that the ones in foo are newer than those in bar:

If yes, then you can just take a diff:

diff -b /path_to/foo/dirA/dirB/ /path_to/bar/ > diff.patch

and then apply the patch onto bar:

cd bar

patch -p1 < diff.patch

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Update: As per OPs updated, he's looking to maintain commit history, above won't work in that case.