Not all multinational banks are the same.
HSBC pretends to do it well and pretends it's smooth. In reality, it's anything but.
SC does a much better job of it.
Citibank varies enormously (more than SC and HSBC) from country to country. In many places, Citibank is a more or less recent acquisition (it was another bank and has been taken over by Citibank). This affects how smoothly different locations work together.
So in some cases, a local bank is a better choice and in some cases going with a multinational bank is better. There's no one size fits all.