Can I use the same power supply for ESD and Non-ESD hand units?

No.

The ESD and Non-ESD hand units have different connectors and therefore require different power supply units.

The 4 Series HOTWEEZERS® and the 2A HOTNIFE™ use the M-10 Power Supply.

The 7 Series HOTWEEZERS® and the 3A HOTNIFE™ use the M-20 Power Supply.