Comparing iPhone 15 and 16e models

The iPhone 16e is discontinued. Unless you are thinking of buying one of those phones directly from the Certified Refurbished section of Apple's online store, I'd be very careful. You might buy a used phone only to discover that it was a useless, possibly-stolen, Activation-Locked "brick'!

The All Too Common SAD Reality of Buying a Used iPad/iPhone – Apple Community

There is an iPhone 17e which is very similar to the iPhone 16e and which is currently available new.

As for feature comparisons, here are some of the highlights.

Compare iPhone models – iPhone 15 vs. iPhone 16e vs. iPhone 17

Note that the iPhone 16e and 17e do not have an ultra-wide (0.5x) camera, do not support USB-C (DisplayPort Alt Mode) (for wired connections to TV sets), and do not support Precision Finding of AirTags. Although the 16e has support for Qi wireless charging, it lacks support for more convenient and higher-speed MagSafe charging.

The regular iPhone 15 has less than 8 GB of RAM, so it does not support Apple Intelligence, and never will.

If budget permits, you might want to look at Certified Refurbished iPhone 16 and 16 Plus models; or at new iPhone 17 models.

This would be on you for the choice you choose. iPhone 15 Base Model, Is the starter of the iPhone 15 series. The Base 128 GB makes the phone $630 retail price, while the 256 GB Upgrade is $730. the iPhone 16e is a budget model starting from $600 for the base 128GB. if you want 256GB, then $700, if you want 512GB, then $800. but I recommand for whats better, I say the newest iPhone. But out of the 2 choices you mentions, I would say the 16e, since it has a better processor and Has better Siri, Voice Isolation and Wide Spectrum microphone modes, and Dual SIM. But if you ask anyone else, they would advise you to get the lastest iPhone, or wait until September for the iPhone 18 Pro and Pro max launch.

OP started a duplicate thread here:

Should I buy iPhone 16e or iPhone 15? - Apple Community