The first thing is you will not be an EMTI employee. you just get employed by some Western companies through them, so it's different. Secondly, taxation of seafarers is different from other professions. In our country the government doesn't tax people who work abroad specialy seafarers, but you might be taxed by the flag state of the ship you are working on, and also by the country of the company. That depends on the flag state country and the company's country. Legally speaking in Ethiopia, if you live more than 183  days out of 12 months in the country , you have to be taxed, but it is not being enforced