Wonder Woman is almost 50/50 right now between domestic and international. The previous 3 DCEU movies were all bigger earners internationally.
You should note the percentage split, not the amounts. I often mention 'foreign multiplier' which is basically just 1 on DC movies, and other domestic biased franchises. Percentages rounded up for reading convenience.
MoS: 44-56, BvS: 38-62, WW: 50-50, Suicide Squad: 44-56
Star Wars TFA: 45-55, Rogue One: 50-50
Transformers and Pirates, and many other franchise have gone from 40-60 back in 2005-ish to 20-80 in their more recent outings.
Transformers: Age of Extinction: 22-78 !!
Pirates: On Stranger Tides: 23-77
Pirates: Dead Man Tell No Tales: 24-76
The point here is that these splits are fairly predictable (TF5 will be 20-80 ish too), and they tell you something about audiences, the absolutes don't matter, because a stinker will affect audiences the same way everywhere. I know that sounds weird, because we seem to think that China likes garbage movies, but that's not the case. The Mummy learned this the hard way.
But now for Marvel's split:
Civil War: 35-65
Avengers 1: 41-59 (2012)
Avengers 2 Age of Ultron: 33-67 (2015)
Iron Man 3: 34-66 (2013)
GotG2 (which is kind of Star Wars-y): 45-55 (2017)
Doctor Strange (2016): 34-66
THOR 2: THE DARK WORLD: 32-68 (2013)
As you can now tell, the Marvel split is consistently 34-66, not nearly 50-50 like DC or Star Wars.
This is what I was referring to by the difference in their split, as these movies appeal to different audiences. And I believe that is due to being more action oriented, since the 'stupid, stupid action' movies are 20-80 split.
The year of release doesn't even influence it much with Marvel. Their foreign multiplayer is therefore consistently 2.
edit:
Btw, considering you have an Underworld avatar, we can also play this game with that franchise.
Underworld (2003) : 54-46
Underworld Evolution (2006): 56-44
Underworld Rise of the Lycans (2009): 50-50
Underworld Awakering (2012): 39-61
Underworld Blood Wars (2017): 37-63
With the interesting part being, that much like Pirates and Transformers before this year, these movies made a very predictable total of 100 million per movie on a 30 million budget.
For Pirates and TF, that number was 1 billion on a 200-300 budget. But you can tell the split and therefore where the money is coming from in terms of numbers, changes over time, despite totals remaining the same.
Interestingly, the latest Underworld made 80 million, which is only a 20% drop from 'franchise average', whereas Pirates dropped a full 33% versus its average on totals. However, Awakenings is an odd exception since it made 160m total, so the drop from that one to Blood Wars is a whopping 50%, if you ignored that the others made 90-110 each.
But the real take-away here is that it went from 50-50 split to 40-60, indicating the increased cash flow from foreign versus domestic.