Yes. This is in fact one of the most common situations. You have a grounded wye 480/277V source supplying delta primaries of step down transformers.
Can a generator wound as a wye be used to supply a grounded B 'delta' system. Yes, but as others have said the generator must not have any _neutral_ grounding or you will create a short circuit.
With a delta wound motor you need the phase differentials to get any torque, but say you connected heating elements in a delta configuration, all that matters is that you have correct voltage between each input. If your load has no "neutral connection" wye vs delta source doesn't matter.
We have wye and delta wound motors out there and we don't normally pay much attention to which type, they will work as long as you have a three phase source with correct voltage. Won't matter if that source is wye, delta, corner grounded, ungrounded, or even the PWM output of a VFD.