Removing EFI partition from external Disk?
EFI partition is a partition that stores boot files for operating systems, but since it is an external drive, it's not needed. When you erase your disk and create a new GUID Partitioning Table on it, macOS will automatically create an EFI partition. If you don't want that EFI partition, you have a few options:


You can erase your disk and create a new MBR instead of GPT. To do this, follow these steps:


Open Terminal. You can use spotlight to find it
Make sure your external disk is inserted. Type diskutil list and identify your disk (in the output you provided, it looks like it's disk1). 
Type diskutil eraseDisk JHFS+ MYDISK MBR diskX and replace diskX with the actual disk's identifier (for example, disk1)
Your disk will be erased without an EFI partition now.

You can use diskpart.exe to partition the disk on Windows. Windows doesn't create an EFI partition.