I don't think that a preamp would ever make one bass sound like another. The choice between preamps, onboard or in a pedal, is worthwhile because of the varying behaviours of each design. The frequency centres, Q, and level of boost or attenuation will vary, as will the features available. Some are no more than bass-boost only, some are 3 or four band semi-parametric, some have switchable, set boost or cuts, some are flat when centred, some introduce an inherent colour.
I rarely bother with onboard pres because they are invariably limited due to space and power limitations, not to mention that I prefer my subtractive and additive EQ either side of a compressor. That and I only once have come across a situation where a buffered signal would have been handy, but a passive DI box solved that!
A 3-band parametric with switchable bell/shelf on the high and low would cover the majority of preamp responses out there, add in variable high- and low-pass filters with resonance controls, and perhaps a couple of additional, switchable bands and you could replicate just about any preamp out there, which is generally how I prefer to do it. However, if I was after, say, a Wal preamp reponse, there would be a lot of sense in having one either on board or in a pedal, for ease of use. Moreover, I really like the old Fender amp pre and the Pultec EQs. Ignoring that they also have valve make-up stages, as much as I might learn my way around a parametric, there is something appealing about the simplicity and vibe of them which makes versions of them worthwhile to have, to me at least.
What I'm lockdown rambling around to is that the preamp and bass are two separate entities, and the pre is ultimately some degree of pre-set parametric. The reductions in functionality will be designed for space and practicality in line with the maker's thinking, which give the pre a certain voice in use. Applying that pre to any bass won't make it another bass, but the response of the pre can be used to alter the voice of said bass in the same way it alters the voice of any bass.