Hi, your game has really cool mechanics. Congratulations on your first jam! I really like the idea of transferring object properties to others. It's a fun idea, and you should definitely keep it in mind for future projects.
I struggled with the controls at first, and I noticed other people had the same issue.
At the main menu, my instinct was to click the buttons with my mouse. I quickly realized it was arrow controls. I also had to cycle through universal key-binds for confirmation, like Z and shift. Listing controls for the menu would've been really helpful and have avoided any initial confusion.
For the actual game, the controls also felt a bit unintuitive. For mouse controls, the norm is usually to pair it with WASD for movement. This makes it easier to press other keys and feels more balanced (so you don't have to juggle to the controls from the arrow keys). Also, it would make a lot of sense to use right and left clicks for extract/insert, as those are actions mostly paired with moving the mouse.
With the 1 key especially, it felt like I was moving my hands all over my keyboard.
Also, indicators would help the player experience a lot. The focus of the game should be the interesting mechanics, not trying to figure out what's a wall and what's an entrance. For telling people where a new room is present, you could use subtle indicators like hanging ledges, particles, a change in color, or anything else you can think of. And for the attachment mechanic, try using a hook to tell players they can latch onto it.
I also got soft-locked several times. Once in the main menu credits, and another time when I was trying to cross the bridge and accidentally extracted the object below me. It didn't go back into my inventory, so I was just stuck. Play testers would have helped a lot in this regard, as they can be notorious for finding the most bizarre bugs you could never think of.
Genuinely though, you had amazing ideas for this project. It seems like you bit off more than you could chew, but you did a lot as a solo developer! With more time, you probably could have made a friendlier player experience too.
Try to focus on the player next time, as the player is what enables the experience.
Anyways, good luck with your future game jams!