Photos program wants to import duplicates in High Sierra OS

The Photos program on my MacBook Pro now wants to import duplicate photos from my iPhone 7+ (iOS 11.0.2). This bug appeared after I upgraded to macOS High Sierra. The potential duplicates appear in the "New Items" section of Photos after the iPhone is plugged via USB. Only photos from previous versions of phones are affected; photos taken since I upgraded to iPhone 7+ this April aren't affected by this bug.

I am not using iCloud and am transferring photos via USB.

When I look at the iPhone photo files with Image Capture, I noticed every pre-iPhone 7+ photo has two files associated with it: the original photo file plus another photo file that's identical, except with an "E" attached to the name (the size is also slightly larger). For example, if the original photo file name is "X01.jpg", there's a duplicate photo file called "X01E.jpg". In contrast, the iPhone 7+ photos don't have the "E" duplicates.

I suspect Photos is viewing the "E" duplicate as a different photo, which is why it wants to import it, even though the photo is the same as the original.

I understand that an "E" file is created when the photo's been edited on the iPhone. However, I've never edited photos on my iPhone, yet there is an additional "E" file with EVERY pre-iPhone 7+ photo on my phone. I've also tried deleting the "E" files off the iPhone by selecting "Delete items after import" then importing them, but the "E" files seem to "regenerate", because if I unplug the iPhone then replug it to my MacBook, the "E" files reappear on my iPhone.

Not sure if this is a MacBook High Sierra bug or iPhone bug (or both) but can it be fixed?