Great advice. Get yourself something like the 7hz (I’ve not heard that one) or the TC zero. They’re inexpensive. At the very least, once you know what you like or don’t like about it, it’s much easier to come back, look at some graphs, read others’ thoughts, and your next set is much more likely to get you where you want to be.If you're a big fan of oratory's EQ — give 7hz Zero a try, he made his EQ profile for them. I would advise you not to spend a ton of money on your first and blind purchase, since you have no idea which sound signature you prefer (OE preference curve usually doesn't correspond to IE curve). Be patient and play around with EQ on Salnotes Zero. This skill is truly useful. There's no magic IEM that would hit your preference curve perfectly.
Compare hundreds of frequency response graphs between IEMs and earphones from manufacturers like Moondrop, Sony, 64 Audio, Fiio, and more.squig.link
As Kysa said, you’ll probably never find the absolute perfect IEM for your preferences, but after having tried 4 pair of IEMs at this point, I have a much better understanding of not only what I want sound-wise, but also a better idea of what I am likely to find comfortable. When it comes to IEMs, fit/comfort is practically as important as the sound profile.
For example, I now know that I have fit issues with IEMs with a short nozzle length (Kiwiears Cadenza, Moondrop Chu). The TCZ and QKZxHBB Khan both have longer nozzles and they are much more comfortable to me. I’m now trying to see if I can find a tip that’ll work with the Cadenzas, cuz when the fit is dialed in, I do like their sound.