I don't think the x-ref is necessary. We don't tend to use them in cases like this.

@@ -14 +13,0 @@
-<pos>&adj-na;</pos>
@@ -16,0 +16 @@
+<pos>&adj-na;</pos>
@@ -18 +17,0 @@
-<xref type="see" seq="1000220">明白・めいはく</xref>

https://en.wiktionary.org/wiki/明々白々
Etymology
Emphatic, reduplication of 明白めいはく (meihaku)

明白	644835	98.1%
明々白々	12330	1.9%


明々白々な事実	200	30.0%
明々白々の事実	228	34.2%
明々白々たる事実	238	35.7%

明々白々は	0	0.0%
明々白々が	0	0.0%
明々白々を	0	0.0%

"明々白々" site:twitter.com 2470
"明々白々を" site:twitter.com　　Of 4 matches, *maybe* 1 is an [n] usage. (and I don't know if it would be considered grammatical...)

Super useful to learn this as a set with the underlying term(and the xref is [ichi1,news1,nf10], which suggests why this fairly unusual reduplication is in somewhat-common use).

I was suspicious of the POS differences with the xref and looked pretty hard at this, but what we had seems fairly correct, even if some usage is uncommon.  [n] at least seems droppable here. There are a couple of very old google book results with a few phrases that might be "pure" [n] usage, ("明々白々を容れず" from a 1904 book on Descartes...), but these are extremely limited.

@@ -17 +16,0 @@
-<pos>&n;</pos>
@@ -18,0 +18 @@
+<xref type="see" seq="1000220">明白・めいはく</xref>

明明白白	894
明々白々	12330

can someone use a bot to reorder entries like this?

@@ -5 +5 @@
-<keb>明明白白</keb>
+<keb>明々白々</keb>
@@ -8 +8 @@
-<keb>明々白々</keb>
+<keb>明明白白</keb>