Are there new rules for non-EU citizens from the Balkans who would like to work in the EU?
No. Although you might have heard information to the contrary, there are no new provisions solely for nationals from these countries. For employment purposes they will still need a visa and a work permit, for which they will have to apply at the German Embassy in their country.
The new Skilled Labour Immigration Act will most likely not enter into force before 2020.
All information on how to obtain the necessary documents for working in Germany can be found on the websites of the German embassies in these countries.
In Albania, Kosovo and Serbia, potential migrants will also find support at the German Information Centre for Migration, Employment and Careers (DIMAK): https://www.startfinder.de