I would say Eevee has a higher potential for high quality rendering because it doesn’t need to be completely realtime. UE4 measures performance wins in milliseconds instead of frames because you generally need at least stable 30 fps (60 fps is preferred when possible). That means there are a lot of cheats to get things that looks pretty good but are also rendered fast.
In Eevee you don’t need 30 fps because it doesn’t need to be played in realtime so you have the ability to crank up the settings. Or, if you need realtime playback, reduce the settings so you get more FPS.
UE4 has been out a long time and things have improved graphically with every release so Eevee has some catching up to do. But the main cons of UE4 is that you are limited to using imported .fbx meshes and animations which means you can’t use modifiers/cached cloth sims and so on.
Sequencer in UE4 which is made for making cinematics has been very rough with tons of minor bugs everywhere so for me it turned out to be a bit of a disappointment. Especially since the animation systems you made in your game don’t really translate into it, instead you’re better off using one-off animations. I think it would be way more powerful if it was more integrated with the game side of UE4 instead of being a separate cinematic thing which has lots of limitations.
That being said you can still make cool things with it, here’s an example: https://www.youtube.com/watch?v=xlaOaHvabH0 (featuring some Blender fracture stuff too!) I think the animation blending is a lot easier to do in UE4 than in Blender (NLA) too.
The main pro of Eevee is not that it’s Eevee but that it’s Blender. It’s basically made for animation, you can bake cloth, particle simulations, use modifiers and so on. Corrective smooth modifier, how I miss you. The pipeline is also easier to handle because well you don’t need one, you just use the mesh data/materials in Blender itself.
There are also tons of Blender specific features like absolute shape keys, crazy addons (like AN) and so on. I also think generally the workflow in Blender is better because of the UI and scripting, some things in UE4 can get tedious very quickly, although this could get improved with python scripting in the next release.