On the tap tempo:
I’m pretty sure you can do this. I’ll have to experiment to work out an appropriate work-flow (much of this will depend on if you’re wanting instant tempo changes in a live setting, or to fashion a tempo track while ‘recording’ a part), but I believe it involves first using the linear time mode while recording. Use a local MIDI transformer to convert your pedal stomps to a MIDI note on a track of its own (also set to linear time). If you like you could even assign that stomp track to some sort of Metronome click sound (You could use a sampler track, or send it to your favorite VSTi drum kit).
You’d want to use another local transformer to filter out your pedal events (or you could just run a quick logic editor to delete them later) for the track(s) that are recording your playing (minus the pedal stomps).
So effectively, you’d be recording 2 tracks at the same time. One holding your live playing, and the other holding your pedal stomps. Later, you could ‘merge tempo from tapping’’ and Cubase would create a tempo track for you. Go back to tempo mode, and hopefully things line up with the tempo grid all ready for possible quantification if desired.
https://steinberg.help/cubase_pro_artist/v9/en/cubase_nuendo/topics/editing_tempo_and_signature/editing_tempo_tempo_changes_unknown_project_track_from_tapping_setting_t.html?hl=tap%2Ctempo
On changing tempo via Continuous Controller:
It think this is possible using a Generic Remote map and a Virtual MIDI port. You’d need to record your live automation on a standard MIDI track which would be diverted into a Generic Remote Map via virtual MIDI port (Use something like loopMIDI if on a Windows PC).
https://steinberg.help/cubase_pro_artist/v9/en/cubase_nuendo/topics/remote_control/remote_control_generic_remote_device_t.html?hl=generic%2Cremote
I haven’t tried it yet, but It also might be possible to use the Generic Remote maps to bind a pedal based CC to ‘tap in a tempo’ during live playing. The catch here is that it’d only work in ‘fixed tempo’ mode. On the plus side, you could again use a virtual MIDI port and route the pedal(s) through a MIDI track and into the Generic Remote map; thus, making it possible automate the process of changing tempos on fly in a hand’s free manner.
https://steinberg.help/cubase_pro_artist/v9/en/cubase_nuendo/topics/editing_tempo_and_signature/editing_tempo_fixed_project_tempo_unknown_project_tempo_from_tapping_setting_t.html?hl=tap
Generic Remote maps offer a lot of not so obvious power user abilities. I’ve discovered a lot of interesting ways to automate DAW features that don’t have dedicated automation lanes using a regular MIDI track, virtual MIDI ports, and multiple stacked Generic Remote maps. Examples include automating things like arming and disarming tracks, launching macros, logic editors, and more.