There are many subtle differences between MIDI 2.0 Per-Note Controllers andVST 3 NoteExpression. The good thing is that plug-in developers do not have to do anything about it. It is the host's duty to translate from MIDI 2.0 to VST 3.
MIDI 2.0 Increased Resolution, compared to MIDI 1.0
MIDI 2.0 achieved a significant increase in resolution of many important values, like Velocity, Pressure, and Controllers compared to MIDI 1.0. Nevertheless, VST 3 still has superior resolution than MIDI 2.0. Plug-ins and hosts supporting VST 3 should make use of these capabilities and should not stick to a 0-127 mindset.
See the following tables to compare the resolution of specific values in MIDI 1.0, MIDI 2.0, and VST 3.