Hi - the instructions say not to cut them, but you can. Some people cut them diagonally rather than across, not sure why but probably to do with the way the delivery system is made.
As you say, you can cut the oestrogen only patched and then, in the second half of the month, cut the oestrogen+progestin patch.
You can also get a 25mcg Evorel patch but would need a separate progestin because it is oestrogen only. The progestin in Evorel Sequi is norethisterone and you can also get it in tablet form to take alongside a 25mcg patch. In case your doctor doesn't like the patch-cutting, it is another option.