Is possibile to install batocera on hard drive partition for dual boot Windows 10 and batocera ?
for end users, no.
the batocera installer targets the whole disk.
i recommand to use a usb key whileinstalling batocera on a hd has no really advantage.
If you're still looking for a way to install batocera on a partition, try making a USB key and then copy the boot partition onto unallocated harddrive space. You can increase the space after the copy is made. It worked for me on Windows 7 and 10..