MIDI has standardised parameters, velocity is one of them
Modular doesn't really have any standardised parameters, you can use available voltages for whatever you like.
In your case, if you are using an envelope generator that has a LEVEL input, you could plug the MOD output on the Nerdseq's track to that input and write values into the MOD lane of the pattern.
Otherwise you could put an envelope through a VCA, and go from the MOD output to that VCA channel to adjust the level of the envelope
Modular doesn't really have any standardised parameters, you can use available voltages for whatever you like.
In your case, if you are using an envelope generator that has a LEVEL input, you could plug the MOD output on the Nerdseq's track to that input and write values into the MOD lane of the pattern.
Otherwise you could put an envelope through a VCA, and go from the MOD output to that VCA channel to adjust the level of the envelope