

No, that is not what I am suggesting at all.
Decompressing the zip on the phone is an inefficient operation, as you are reading and writing to/from the same storage device. It’s much more efficient to forgo the zip altogether and just transfer the files from one device to the other. No zipping whatsoever.
As said in other comments, it’s MTP that’s the issue here. Just use USB mass storage. MTP blows.



This external drive I have is just USB mass storage. It’s using the USB protocol and shows as removable external storage, same as a flash drive.
Removable storage is not the issue here. There is no significant overhead introduced by having removable storage with USB mass storage protocol.
OP is forced into using MTP which does suck and adds overhead. This is not the “normal” way of transferring to me, that would be USB mass storage.