Hi, there!
Can VST plugin produce signal louder than 0 dBFs?
Can it make overload on input of next VST plugin in chain?
Of course, actually most VSTis do with just their standard presets 
Yes it can and will overload your signal chain if it’s too hot. Use the gain slider in the pre section to calm it down to a proper level. Most plugins expect a level of -18 dbFS. The whole thing is called ‘gain staging’, lot of topics here and some good stuff on Youtube that explains what’s going on.
Thank You, marQs.