The answer currently is no. You will not encounter any issues hiring a EU citizen. You will just need to go through the same processes as you did so far.
There will be no change until 31st of December 2020.
In the event of a “no deal” afterwards things will probably get more complicated. As an example your employees from EU might need to acquire a working visa.
Our champions in the EU and UK are looking closely anything Brexit and we will get back to you with any new employer specific information.
In the meantime we will be more than happy to answer any other questions you might have.