I then return the micro-SD card to the Floppy EMU and boot up my SE/30 and have access to the newly copied files.

When finished I 'unmount' the HD20 file from Sheepshaver, and quit Sheepshaver, and then copy the HD20 file back to the USB-mounted micro-SD card and it overwrites the old file. By default, SheepShaver give you access to a mounted drive named 'Unix' which is in actuality the Shared folder inside your Users folder in your Home folder, so you have immediate access to files downloaded from Macintosh Garden that you move to this folder on your Mojave Mac. those files I want to access on the HD20 when connected to my SE/30. I then use SheepShaver to copy/paste etc.

I then run SheepShaver and attach the HD20 file to it as a mountable drive. I them copy my 'HD20' file from the Floppy EMU to my Mac Mini desktop, because I have found attempting the next few steps directly to the USB-mounted micro-SD card is unstable when I try to read/write to it directly from SheepShaver.

I mount my micro-SD card from my Floppy EMU on my Mac Mini High Sierra.

Mac system emulator