The file content will be the same after copying from ext4 to NTFS.
But the permissions and ownership are often modified.
If the performance depends on permissions or ownership, there might be problems after copying.
There may be protection against executing programs from an external drive.
If you try to use the file in the other operative system (Windows), you cannot expect an executable file or symbolic link to work, but data files, for example documents, pictures and video clips can be expected to work.
Edit:
I tested with executable files, the compiled program htop and the set of shellscripts mkusb.
Operating system: persistent live Ubuntu 18.10 created with mkusb.
File system: Partition number 1 with NTFS, mounted as /media/ubuntu/usbdata
Commands:
sudo add-apt-repository ppa:mkusb/unstable sudo apt install mkusb usb-pack-efi sudo apt install htop which htop cd /media/ubuntu/usbdata ln -s /usr/bin/htop link-to-htop-in-ntfs ./link-to-htop-in-ntfs ln -s /usr/bin/mkusb link-to-mkusb-in-ntfs ./link-to-mkusb-in-ntfs which mkusb-nox cp -p /usr/sbin/mkusb-nox copy-of-mkusb-nox-in-ntfs ./copy-of-mkusb-nox-in-ntfs ln -s /media/ubuntu/usbdata/copy-of-mkusb-nox-in-ntfs link-to-copy-of-mkusb-nox-in-ntfs ./link-to-copy-of-mkusb-nox-in-ntfs cp -p /usr/bin/htop htop-copied-to-ntfs ./htop-copied-to-ntfs
These commands work (while still in the persistent live Ubuntu 18.10, which is running in an external drive). In other words, executable files and symbolic links work from an NTFS file system.
But in some installed systems, execution of programs in external drives is prohibited for security reasons. This can be changed according to the following link,
Mount NTFS partition in a USB drive with custom permissions and owner