What nerve blocks/anesthetic blocks work the best for bilateral leg neuropathic pain?

Depends. on where the problem lies... If epidural steroid injections are not helpful, then injections like sympathetic blocks can be helpful. Other options include spinal cord stimulation as well.
Lumbar blocks. Lumbar sympathetic blocks, root blocks can work. If they don't spinal cord stimulation is an option.
Depends... On the nerves that are irritated and the location of your pain. If pain is widespread all over legs and reaches your toes, a caudal epidural steroid injection with a large volume to cover a large area of spread in lumbar spine might help. If symptoms are more localized, a more selective nerve root injection may be helpful.