she could easily create a trade company that will dominate trade with the east. It is something that can be done with a few actions form Mathilde.
I disagree with a lot of the stuff you said but most of it at least has some shades of grey, this though is pure fantasy. No, neither she nor the company will be able dominate one of the biggest trade cashcows in existence. It's an incredibly tempting pie with quite a few significant stakeholders expecting their cut, even just significantly expanding the share she has interests in would take quite a bit more than just a few actions.