Unreal Engine for Low End Smartphones and PC

TLDR: Title, is it possible?

Before, I am sorry if what I’m about to ask has already been answered. (I tried searching the forum and the answerhub, but the filter range is just too broad, really)
I’m a newbie software developer, and I looked at comparisons and EULAs and TOS etc on the available engines. Unreal Engine kind of attracted me in the end. Unty is stingy like yay and Flsh is more or less abandoned, while others are mostly unheard of.

I read the basics and I know Unreal Engine projects can be made for smartphones, but is it possible to make a game for low-end smartphones and PC?
My friend kept telling me that games made with Unreal Engine usually left his laptop really hot despite only idling on the main menu. I was wondering if I should or shouldn’t try using Unreal Engine to build a game.

When I said low-end, I mean really low-end, like a phone with 512mb RAM. Not 3d is fine, but can a 2d game run on that kind of device if I use Unreal Engine?
There are settings for performances and also optimizations; I know, but if they’re all maxed, can it be played at all?

Thanks before and sorry for the longpost!