Hi.
No idea what e-reader you will use to read that EPUB but you might check my software -
http://kcc.vulturis.eu/
With
Horizontal mode on all double pages will be rotated. Otherwise they will be split automatically.
The only problem is specifying a proper screen size. If your hardware display book on entire screen it will be not a problem... but if for example there is progress bar on bottom then you need reduce target height.