Just speaking in general to all the discussion about splitting/retrofitting Euro's etc, after weighing options for almost 2 years, I personally wouldn't and would advise, with some exceptions, against importing Euro's *brand new*, of any brand, with the intention to immediately split to use for a project... let me explain my logic.
First, even the replicas aren't "super" cheap and take weeks to import. They also get handled a lot being shipped 2/3rd of the way around the world. Cars245 doesn't drop ship from Taiwan at all, they all get shipped from Taiwan to Latvia and then all the way to the US. So, we know many arrive damaged as it is, and if not, I think they are likely going to be more susceptible to damage trying to split/modify after all the shipping. Especially with more sensitive stuff packed into there like the controller boards and leveling motors (that we can't really use at all) that the reflectors don't even have is unneeded complexity. Why mess up something that's not easy to replace within a couple of days?
Cheap aftermarket replacement, TYC are like $84 each side new in both silver and black interiors available or used/junkyard OEM reflectors would be a better start to mod. I think our regular reflectors are common across all Fiestas, so very common to find cheap anyway. So why not just go that route if you are going to upgrade almost everything anyway and have far fewer complications? Like what would be the point of going Euro at that point anyway? The reflectors also have the US legal amber corners if you want to stay legal.
With a cheapie reflector to start with, you can do whatever custom DRL, high beam retrofit, low beam projector upgrade, etc. Sounds like maybe even the pro's would prob be more familiar working with those as well. So while maybe a little more reliable to split/upgrade with to begin over a Euro, they are also much lower cost and easier to replace if all goes south, LOL, amirite?
Of course, one specific exception could be if you really specifically want the factory chrome instead of the amber on the US sides. Keep in mind Premium Auto Styling makes nice corner blackout decals that fit the US ones better than Euro's too, see my avatar pic... what you can't see though is the pass side decal doesn't fit the Euro quite perfectly but I didn't want all that chrome with my dark themed car so that's why I used them. With reflectors, you can used them to cover the amber as intended and even leave the little bulb out if you want or maybe there are some universal DRL's that can plug into that socket maybe? If not then would still be easy to use that marker power wire to power an added universal strip DRL. May be pretty easy to go further and do a single wire mod, similar to Euro's, using the wiring diagram to split off power separately to the added DRL brow, and have what was the combo DRL/marker and turn signal becomes just the blinker like on Euro's... Not even sure if universal DRL strips can handle 2 levels of brightness switching. So if not, or to keep it simpler just tap into a DRL power in the harness and maybe add switchback DRL/turn signals... Also, like doing the simplest auto high/low DRL's on the Euro's, you can also run power off the fuse box with an Add a Circuit to our one open F27 spot ('16+) that gets switched on and off with ignition if you need to... lot's of options!
Just my $.02 of ideas... any thoughts?