Site migration, GEO IP redirects

Hello,

Currently we have 2 websites which will be merging, example: abc.com and def.com will merge and migrate to a third domain: xyz.com.

abc.com also has a translated version: abc.com/fr however that subfolder will be redirected to another website in the same language. So only the English version of abc.com will be going to xyz.com

xyz.com will have subfolders to target different regions (all English language) xyz.com/eu will target EU countries and xyz.com/global will target users outside EU countries.

A GEO IP redirect will be used so anyone outside the EU will be served xyz.com/global and anyone within the EU will be served xyz.com/eu.

There is some content overlap for yxz.com/global & xyz.com/eu so want to avoid duplicate content (can be localised but won't be totally different as it's the same product)

Challenges & questions:

1. For the migration, usually I‘d use the Change of Address tool in Google Search Console from abc.com and def.com to xyz.com. However, as the /fr subfolder on abc.com will be redirected to a different website, does this mean this will no longer work? Also, with the new domain targeting 2 different regions, does this also mean the country targeting option shouldn’t be used?

2. With the new website and subfolders targeting different regions through GEO IP redirects, I’m unsure what the best way to tell Google which version to index for which region. Would HREFLANG be enough and also resolve the duplicate content issues on the respective pages with the content overlap? Or canonicals.

I understand this set up is not necessarily the most ideal way to go but it is what is happening so I am trying to ensure the least negative impact for SEO.

Any advice or ideas are greatly appreciated!

Cheers, KJ