It depends upon the specs for the power supply. Switch mode supplies for example are often designed to work from 50HZ to 400 Hz with a similarly wide voltage input range. However not every supply can handle that. In the same way transformer based supplies can be multi voltage and even specced for 50 Hz operation. In a nut shell you need to read the documentation!
As for europe I’m pretty sure everything that is needed for a CNC can be found there. It might not be cheap or easy to find but the industrial base in the area kinda says that the hardware must be available. If you want to DIY a power supply for your drivers things like capacitors and rectifiers have to be engineered (sized) for what you are building and they can be purchased anywhere. The real trick is getting quality components, especially caps. Sadly I can’t help beyond that as I only know USA suppliers and a few international sources.