Yes—if your goal is simply to preview light direction and shadow placement, a cheap continuous lamp can work as a basic modeling light. A clamp-on LED or reflector lamp placed from roughly the same position and distance as the speedlight can help you visualize where the flash effect will fall.

That said, this is mainly useful for placement and angles. Unless the modeling light closely matches the flash output and spread, it won’t be truly proportional, so it won’t perfectly show the final lighting ratio or modifier behavior. Putting a small continuous light inside a softbox may help somewhat, but it’s still only an approximation and can be awkward.

A simple technique is to use one movable lamp as a placement/modeling light: put it near the camera or move it around the subject until you see the look you want, then place the actual flash/modifier there.

If you’re working mostly in studio, mains-powered studio strobes are the more suitable long-term solution, since they typically include proper modeling lights and more power than speedlights.