I agree that it is useful to actually know how to get a better DB-like sound from an EUB.
First and foremost, IMHO, is having a 3/4 scale and high-quality DB strings that produce the kind of tone you want - the sound of the string is what is being amplified on the piezo, so this alone gets you all the way to sounding like an amplified DB. DB strings are expensive, and they are extremely different from one another - so feel free to spend all your money exploring this step and ignore subsequent suggestions.
Second - there are IRs that you can load into pedals, models that you can load on modelers/amps, and various other forms of digital trickery to employ that are quite effective. The Yamaha silent bass has this stuff baked into it already, but there are lots of ways to hook it into the chain for any EUB. It's for real, too, I literally cried when my Fender Studio 40's "Acoustic Sim (3)" setting made my EUB sound like my old orchestra bass. It's very effective, but yet another rabbit hole.
Third - on the analog side, careful EQ-ing on a good acoustic preamp (Fishman products being the baseline standard of quality, probably), and a touch of room reverb can get you pretty close. Also, if you got an HPF, this is one of the rare circumstances where you may want to turn it down or remove it from the chain, because a lot of people associate the DB sound with the subs and boominess. I still like the HPF for my sound, and I don't like the boominess - but I also don't like muting an EUB, so my opinion isn't the same as everyone else's, maybe that's the sound you are going for.