You should be aware that using foreign citizens' labour in Ukraine is possible only with the special permit. Employment permit is needed also in case if you appoint yourself as the director of your company. Yes, there is such a rule in Ukraine.
When you start a company, you need to have a director before it's registered. But you can not get a work permit before the company is registered, therefore, you need to have only a Ukrainian national to be appointed as a director before the company registration in Ukraine and some time after, during the time period of getting the work permit in Ukraine for yourself.