Yes, no problem at all.

Nebulb can also be used for simple image stacking (without alignment of any kind) for which there is a specific "Preset":

If you select the "Simple Stacking" preset Nebulb performs a stacking of all images (without any star alignment) with the only goal of reducing the noise present in the images. Therefore, in this case it is not necessary to define any mask for the sky.

In addition, prior to stacking you can also activate the luminance and color noise reduction options in the "Preprocess" module:

By activating these two options, together with stacking multiple images, you can achieve a very large noise reduction.