Most "official" sites (including DMM and Caribbean etc and jp.wikipedia) won't list both censored and uncensored filmography. The "thin blue line" of legality force them apart.
Many unofficial sites (Akiba Online, JAVLib, Javbus) do cover both and if you search by an idol's name both type of vids show up. But almost none of them are comprehensive enough to be called "filmography", the problem is still the same: illegality.
it very difficult to find their uncensored one (found 1 or 2 titles but that's it)
There's a very good reason for that. Most censored idols (as you said, "
stars" let's use the working definition a "star" is someone who released more than 10 solo vids) ... So the vast majority of "stars" who ever make uncensored vid only made 1 or 2 uncensored titles. A lot of them even do "double release". Say they shot one 60 mins scene, release it for online sale. A few weeks later, shoot another 60 mins scene, release it for online sale. Wait a few months, paste the two scenes together, design a box art (as if the two scenes make up a coherent film) and release the 120 mins vid as an uncensored DVD under a modified title.
Another common practice is change idol's name when jumping into the uncensored
sea. Typical for a performer with low ranking. Say performer X has not yet established her stardom in censored JAV (not many solo works, unimpressive debutante etc) or an older veteran whose fan/customer drawing power has long been spent (more than 6 months only release as planning performer and/or uncredited). If she wants to make some cash in uncensored, it maybe that faking as a fresh face/debutante is more profitable than using the recognizability of her censored persona/name. I.e. her existing JAV name is worth less than a no-name. Usually the Japanese bloggospere very quickly could id her, but it's more difficult in the English web to track these topics/posts.