gg5, prog, luminous, wisdom

All the JEs have "Amazon". I think it's OK.
I don't think it's "dated" in the sense we use it. Neither shinmeikai nor sankoku describes it as 古風.
I don't think the x-ref is needed.

@@ -12,3 +11,0 @@
-<xref type="see" seq="1285560">豪傑</xref>
-<xref type="see" seq="1285560">豪傑</xref>
-<misc>&dated;</misc>
@@ -17,0 +15,2 @@
+<gloss>woman of strong character</gloss>
+<gloss>Amazon</gloss>

ヒロイン	2656259	98.8%
女傑	28970	1.1%
女丈夫	2045	0.1%

No mention of 女傑 on the wikipedia page for Amazonians.
https://ja.wikipedia.org/wiki/アマゾーン

sankoku: 女性の豪傑

https://www.wordreference.com/jaen/女傑
heroine n	(courageous woman)	女傑、英雄的な女性 名

https://dic.pixiv.net/a/女傑
豪傑な女性の事

Summary: "rarely used, not taken as a complimented, understand it, but don't use it"
https://gakumado.mynavi.jp/gmd/articles/34279
ジェンダーレス社会になりつつある現代、女傑という言葉を使う人はあまり見なくなりました。
女傑という言葉が「女性としては〜〜」のように「女性のくせに」のようなニュアンスを持ちます。褒め言葉としては、馴染まないですね。
自分で使うというよりは、誰かが使ったときに意味がわかる程度でいいでしょう。

女傑って褒め言葉？9/28スタート・NHK連続テレビ小説「あさが来た」
https://view.cafe/monopoly/a-new-day/6107

Listed in the wikipedia article for "heroine".  Considered a crossreference to ヒロイン[2] but decided against.
https://ja.wikipedia.org/wiki/ヒロイン
女性の英雄
勇気・実績・人格に優れた女性。オックスフォード英語辞典でも解説されているように、「ヒロイン」の意味は基本的に、非常に勇敢なさまやとびぬけた実績や人格に優れた称賛の的となる女性のことである[2]。
よって、ヒロインは「女性の英雄」への呼称である。日本語には「女傑」「女丈夫」という言葉もある。

A novel-and-a-half defining what a "person of character" is in English(i.e. much too vague to be useful)
https://www.philstar.com/business/2016/07/16/1603248/become-person-character#:~:text=A person of character values,it was attained with honor.

I don't see any support for "Amazon" (as in Amazonian), *except* that there was a horse named ヒシアマゾン who was described as a 女傑(see last comment). "woman of character" seems unused in practice as a gloss, and very vague in English as to what it might mean. (my understanding of "person of character" is far more broad than what 女傑 would seem to imply). 

I find the gloss "brave woman" perhaps unnecessary.  The daijs definition references 女丈夫, and "brave woman" may have just been copied backwards from there.

Several resources, sankoku included, say simply "female 豪傑". 

Multiple online sites discussing the term indicate that it would not come across as a compliment in modern use(in particular, with the nuance of "pretty impressive, for a woman" and or "having masculine attributes"), and as such I think [dated] is possibly appropriate. Image results are mostly historical anime. Definitely used to describe historical figures, but here, for example, is a government reference recommending against its use for modern inclusivity reasons:

チェックポイント2：男性または女性だけに使われることばに注意し、男女どちらにも使われる表現に心がけましょう。
https://www.city.gifu.lg.jp/kurashi/jinken/1003438/1003520/1003526.html
...
例
女だてらに、男勝り、女々しい、女傑、才女、才色兼備、出戻り、職場の花・・・など。

Key example comment on modern (dis)use:
https://detail.chiebukuro.yahoo.co.jp/qa/question_detail/q13177363268
現代では普通、女性への褒め言葉にはなり得ないので、どうしても歴史的な言葉になってしまいます。

I wouldn't mark this as [dated] based only on a generic government blurb on gendered compliments, but combined with other commentary(refs indicate you should understand it, but never use it yourself), it seems this is not a word that should generally be used to describe a woman today.

it seems the related 女丈夫 would probably get [dated] for similar reasons. See for example:

https://gakumado.mynavi.jp/gmd/articles/34279
女傑の類義語の代表格に「女丈夫（おんなじょうぶ）」がありますが、こちらも現代の価値観にはあまり馴染みません。

Perhaps not unrelated, it seems that competitive female horses still get this term applied to them. (Google news search is full of horses and horseracing articles)

@@ -11,0 +12,4 @@
+<xref type="see" seq="1285560">豪傑</xref>
+<misc>&dated;</misc>
+<gloss>heroine</gloss>
+<gloss>great woman</gloss>
@@ -13,3 +16,0 @@
-<gloss>heroine</gloss>
-<gloss>lady of character</gloss>
-<gloss>Amazon</gloss>