4 of them needed business expertise and 3 of them were immediately solvable.
If you only have Excel in your toolkit, here’s a quick way in which you can address them in a relatively painless way:
(2) same person, different spellings
(e.g. TENEVA ANGELINA in 1 system vs. Teneva, Angelina in another)
(3) use of different names
(e.g. Nederland in some record entries vs. Netherlands in others; Great Britain in 1 system vs. United Kingdom in another)
Happy VBA coding!