It is likely that EU countries that possess this weapon (VETO) will require something from Romania and Bulgaria to take certain actions in order to gain approval for entry into the Schengen zone, as is typical in such cases.

Additionally, there have been instances of EU countries using blackmail tactics towards other countries, such as Bulgaria towards North Macedonia for starting EU negotiations and Hungary toward European Union to send help toward Ukraine in order to gain access to European funding and other resources.

Another way some EU countries have exerted their power is by using their veto rights in the EU Council to block decisions and legislation that they disagree with, regardless of the support it may have from other member states. This can be seen as an abuse of power as it can prevent the EU from functioning effectively and that needs to STOP.

Note: You have map where Croatia is not Schengen zone member :)