In the elliptical style of dictionary entries I don't feel the need for a N or NP with "esp.", but it's fine to have them.

I'm not exactly sure why but I feel that "esp." needs to be followed by a noun (or noun phrase). Maybe it's because "especially large and double-edged" reads like "particularly/very large and double-edged" to me. That's why I changed it to "usu." I agree that "esp." is more suitable here but I think the gloss would need to be worded like this. (Alternatively, "esp. one that is large and double-edged").

@@ -27 +27 @@
-<gloss>sword (usu. large and double-edged)</gloss>
+<gloss>sword (esp. a large, double-edged one)</gloss>

with "usu" I get the impression we're talking about a specific type of sword (one that is usually large and double-edged) rather than a 
general category of swords (but especially ones that are large and double-edged)

I don't mean to be arguing over small details, but isn't "esp" better than "usu"? It can be used to refer to all kinds of swords, but 
especially large and double-edged ones.

(also just realized the typo "double_d_-edged" which somehow managed to by unnoticed throughout all these revisions :))

@@ -27 +27 @@
-<gloss>sword (usu. large and doubled-edged)</gloss>
+<gloss>sword (usu. large and double-edged)</gloss>