How can I use the Pokemon trademark legally for commercial use in my country?
That’s what makes it legal for you.
One of the best benefit of trademark registration is its assignment by owners. Same, applies to this mark as well. The owners of Pokemon may provide you a licence for using its name or characters for limited or specified purpose.
Simply connect with the owner or its attorney with your proposal and requirement to call it an authorised use.
You will need to enter into an agreement called Licence Agreement (type of trademark assignment).