Stealth aircraft like the F-22 and F-35 have very low radar cross sections. These planes have angles of their fuselage set-up in a way to deflect radar signals. As far as I understand another stealth property is that the aircraft itself is relatively flat. When it comes to maneuvering and for example rolling the plane do these features still apply, as the "flat" effect is pretty much gone? So how does maneuvering affect radar detection?
RCS depends on the aspect presented to the radar source, so an aircraft can offer a low radar return from one angle and a large one from another. How much the RCS changes by depends on how much work went into optimizing the airframe from all sides.
Since reduced RCS tends to be at odds with aerodynamic performance, not all sides of an aircraft will be optimized, which will affect mission planning: with proper intel, an aircraft can plan its ingress and egress vectors in such a way to present its "best profile" to any hostile radar installations.
As an example, compare the F-22 with the Su-57. Both airframes have had some low observability built into them, but to different degrees. In particular, the rear aspect of the Su-57 is pretty conventional, suggesting that for whichever reason (funding, time limits, serial production costs, contract requirements, etc) it was deemed acceptable to have a larger RCS from behind.