In more depth:
On your MIDI track, insert the MIDI Insert “Transformer”.
Open the Transformer.
In the top section (Filter Target) add a new line (with the + at the bottom of this section).
It should read “Type is Equal Note”.
That’s what we want here - this will ensure that the transformer only works on note data, not pitch bend or controllers.
Then in the bottom section (Action Target), hit the + to add a new line.
Change the line to read “Value 2 Multiply by 2”.
This will multiply the velocity (Value 2) of the notes by 2, doubling them. Anything coming in that’s above 64 will be capped to 127 anyway.
You may want to save that as a preset so you can recall it quickly.