According to Famitsu Magazine in Japan, Serah and Noel of Final Fantasy XIII-2 will be getting Mass Effect 3 costumes some unknown day for some unknown price. It's also unknown if these costumes will be sold separately, sold as their own DLC pack, or if they will be part of another DLC pack. As for what these costumes will look like...we don't know that either. If the latest costumes as depicted above offer any hints, Noel will probably have N7 armor and Serah will dress like an asari dancer.
I was not a fan of FFXIII-2, but I have to admit that the overly ridiculous Mass Effect fangirl in me really wants these costumes. Maybe then I'll find some additional motivation to unlock all of the paradox endings.