This appears to be the trash directory created by mac OS. It should be safe to delete, and will be re-created when necessary.
Do you know how external flash drives manage deleted files? Do they have their own recycling bin? Would the flash drive make another Trashes folder on its own, or should I make one? I deleted a file and didn't find a Trashes folder.
The flash drive doesn't manage deleted files – it doesn't even know what a file is. Whether internal or external, SATA or USB, the only thing it really knows is "sectors" – 512-byte data blocks that are numbered from 0.
All file management is handled by your operating system, whose "file system" decides which files to place in which sectors. Each file system (e.g. FAT32, APFS, NTFS) has its own way of doing that, and the drive doesn't actually need to understand any of them.
As for deleted files, that's usually the job of the OS graphical interface (the file manager app, e.g. Explorer on Windows). Each operating system has its own convention about where to place deleted files:
- Windows will create a directory named
$Recycle.Bin
if it's a "fixed" disk (e.g. a portable USB HDD), but will not use a trash at all if it's a "removable" disk (e.g. USB pendrive or SD card).
- Linux will create a directory named
.Trash-###
with your numeric UID.
- macOS will create a directory named
.Trashes
with subdirectories for each UID inside.
- And in many cases (e.g. when deleting files through Terminal or Command Prompt), the file is simply deleted outright without using a trash.
Because there is no standard path, the trash directory cannot be pre-created when formatting – it is not "built in" to the filesystem structures – instead it is just a regular directory, and each OS will automatically create it when necessary.