You could make a new auto material Let's make an MMO in UE4 - Part 4 (Landscape Material) - YouTube
Which basically blends two (or more textures) based on an “up” vector and the local normal
(this is done by taking the dot product of the two vectors which gives the sine of the angle between the two vectors multiplied the individual lengths)
Assuming for simplicity that the axis of your O’neil cylinder is the X axis then the up vector becomes the local landscape position with x set to 0 and then normalized (forced to length one)
