Would my overlapping second toe and severe bunions cause me to have knee pain and leg numbness of the same leg? I have no pre existing leg issues.

Pain not related. The only way that your knee pain would be related to your bunion and/or hammertoe, is the fact that they are making you walk differently due them being painful themselves (bunion/hammertoe). Consider them being indirectly related. The numbness is totally a different issue. That could be something originating from your back. Consult a professional.
Unlikely . Unless this causes a major change in your gait i would look for another cause. I would look for musculoskeletal causes, vascular causes and neurologic causes. Your evaluation would be directed in these areas.
Bunion. most bunions are caused by flat feet. when the foot flattens or the arch collapses the hip and knee internally rotate, and the pelvis tilts forward. This could have some effect your knee pain and could be creating a pinched nerve - sciatica on that same side. See a foot/ ankle specialist - Podiatrist - for a work up. A good arch support may help .
Pronation. Without a physical exam or picture to diagnosis it seems as if this is congenital/pronation problem causing the bunion and overlapping second toe. This will throw out the skeletal tree or the "q" angle which is a line drawn from the medial malleolus to the knee to the external part of the hip. Should be straight. If not and bends either way at the knee it will miss align your kneecap and lower back . Orthotic control may be helpful however surgical correction maybe an idea also.