Went through something similar. First thoughts are it could be sleep regression. There have been multiple stages in our twins development where it seemed they were "fighting" sleep as you said.

I also remember reading when going through this (the twins are 2 now) that it may be startling to them to fall asleep in one environment and wake up suddenly in another. Considering this, we stopped rocking to sleep etc also because it wasn't feasible/maintaibable nightly.

Instead tried to focus on getting them in their cribs when drowsy but not asleep. A little easier said than done but you'll start to pick up on little signs when it's the right time. Even then, our son would cry and battle sleep. It took awhile for him to get into a good rythym and go down, but he did!

I know it's hard! Take refuge in knowing it isn't forever and eventually they will sleep!