If you just want a yes/no answer then at least Lakka for x86 CPUs is "just" a Linux distro, if you have any experience creating a bootable USB you will have no problem at all.

I have no experience with RetroPie but their website does mention x86 solutions, so I would hazard a "yes" but don't treat that as definitive.

Not to second-guess you too much but what systems are you trying to emulate?

You can probably cheap out if you're only interested in "retro" emulation, for example a used Nvidia Shield can easily be found around $150. The Android UI is very welcoming with big and colorful icons so I wouldn't bother with a frontend, but if you really want one then you can still get one from the Play Store, like Dig.

And if you want to emulate newer systems, it's likely your PN50 will be so powerful you would waste it by not installing Windows so you can emulate more recent consoles, and even use ReShade on top if you like.

Whichever you get, I would still add a wireless keyboard/touchpad like the Rii8 or the K400. It's just infinitely superior and more functional than most other options.