This isn't specific answer to your question, but may still be somewhat useful. In plumbing, you are only allowed so much change in direction before you are required to have a cleanout. I don't remember the total angle...but, I think you're close if not over that . Second, it will probably work, but it would be better if it were directly under then drain in the shower. The longer the pipe is before the trap, the more opportunity there is for soap scum, hair, oils, etc. to potentially accumulate on the inside of the pipe. The trap is what stops any of those nasty smells from coming out of the drain, so ideally, the shorter it is, the less of that would be available to smell.
Third, while plumbers do it a lot, you NEVER should notch or cut the top or bottom edge of a joist! Think sort of like an I-beam...I'm sure you've seen some (a truss is similar) that are quite small in the middle, or maybe even a lattice - solid lumber is similar. It is the top and bottom that provide the strength, the middle is mostly (not entirely on a solid wood lumber) there to hold the top and bottom edges in place. The strength comes from the compression on the top being offset by the tension on the bottom when there is a force applied (gravity) pushing down. Code allows any holes to only go in certain places in a joist (essentially, in the middle between the top and bottom), limits how close to the end of a joist they can be, and also limits their size. Especially underneath a shower that could get quite heavy, you don't want to lose that strength. You need to reinforce that cut joist. One way around that would have been to box it out with some headers and joist hangers...then, you'd have an open area and wouldn't have needed that offset.
A plumber would know the max angle before cleanout requirement, whether that is acceptable, and should know about notching joists (but it seems to often be ignored!). An inspector might have something to say about it (did you pull or have a plumbing permit pulled?). A licensed plumber should produce work that will pass an inspection, but that is also why you get a permit to get a second opinion and verify it was done right. Other than the joist, I'm not sure.
