I've been thinking about something similar.
The growl can be gained from a wenge neck but it can sound a bit boxy unless tempered by a harder wood like rock maple. Soft maple can also give it too but it's not as deep as wenge more of a purr than a snarl. My Spector NS5CR is made with soft maple and it purrs nicely on stage regardless of hands or pickup position. The later Euro basses with the Alder/walnut/maple sandwich aren't as satisfying to play for me personally. I had a Euro 6 for a while. Ken Smith basses achieve it with maple and bubinga but it doesn't sound as focussed as either wenge necked Warwicks or through necked, all maple Spectors. Ken deliberately avoids making the neck too stiff, instead relying on a massive ebony fingerboard to provide the structural stiffness - I think the same is happening with my Spector NS5CR too. Consequently I found it hard to get super low (like...graphite neck low) action on my three Smiths and the Spector but they were still very playable. Fender J and P basses sometimes achieve it with a combination of light swamp ash (for jazz) or light alder (for p basses) and well seasoned hard maple that is a little on the softer side. Dingwall do it with a combination of ash+alder that meets specific weight criteria and hard maple necks. Status did it with their Series II basses using pickups and electronics. Jaydee do it by using mahogany in the necks and bodies and relatively flat response pickups.
There's no single way to do it, it's like mixing different ingredients to get the same flavour. You can do it with fingers over the bridge pick up and plucking very aggressively on many (not all) basses but some people don't feel comfortable playing that way.
GK amps get you close with their boost control too but it's achieved in a different way. It kind of relies on an interaction between bass and amp and the mid prominence being achieved with bass, hands, the boost control and filtering by the speaker itself. Hard to achieve at low volumes but sounds glorious at performance. I'm not aware that GK offer the boost function in a pedal because it relies on passing the boost onto the woofer while leaving the tweeter highs unaffected.
What is happening in both cases is that a very narrow band of mid frequencies (around 250Hz) are getting prominence. The easiest way to do it in pedal form is with a parametric eq or a band pass filter pedal but it has to be a pedal that does an extremely narrow band of boost. So narrow that it doesn't actually affect the sound of the bass in any other way. I've done it with the eq on a mixing desk and hoped to do it with a parametric eq...which is why I actually bought an Empress Parametric eq precisely for this purpose.
But even that doesn't get narrow enough so it sits on my guitar board in order to give strats more bite and shimmer. The Empress boys actually sent me a way to mod the pedal so the mid band was narrowed further but I haven't had time to plan it yet.