Tax residency of business vs Place of effective management

Hi!  I am living in Lisbon for 12+ months with my family and planning to get a proper residence permit here, pay taxes etc. Although, in the first place I am a citizen of a third country outside the EU.

In terms of business I am a director/shareholder of a company located in Estonia, but also planning to establish a company in the UK. Although, I do not have substantial links to the UK, I can just fly to visit events there etc.

100% Portugal will be interested in my personal taxable income.

Although, I have no clarity what are the odds that Portugal will check such corporate structure:

• UK company (to be established) paying income tax in the UK
• another company in Estonia (established almost 10 years ago) also complying with local laws

In my understanding, there is a risk that Portugal may consider one of the entities or even both as tax residents in Portugal > so the foreign companies will be liable for the Portuguese corporate tax rate.

What does trigger Portuguese tax office to check corporate structure? I never heard of such cases, although the risk seems real.

Can Anti-Tax avoidance rules be applied to my case?

Do you have any similar experience? I am interested how that turns out in the real world. Obrigado:)