I’d say definitely Japan, this article has photos of several types of imported steel (Nanbantetsu) from the late 1500 - early 1600s and kept in a shrine since, two of them look to be crucible product and have wootz-y chemistry, as far as reported in the article.
日本刀の鍛錬性に及ぼす南蛮鉄のリン含有量の影響
Effect of Phosphorus Content of Nanban-tetsu on Forgeability of Japanese Sword Making
鈴木 卓夫
Suzuki Takuo
Vol.90, No.1(20040100) pp. 43-47
The Iron and Steel Institute of Japan (ISIJ) ISSN:00211575
http://ci.nii.ac.jp/naid/110001457670/en/
(no, I don’t read Japanese, fortunately the photos, figures and tables are in English)
Hyotan and koban in particular look like semi-processed wootz ingots.
The best references I’ve found for mining, sword making and trade info are “Persian Steel, The Tannivoli Collection” with quite a lot of info on metal trade and manufacture in Persia, and “Medieval Islamic Swords and Swordmaking” the new translation of al Kindi’s 9th Century description of where and how various swords were made, he specifically mentions indigenous production of Khurasani swords; I think that is called Kurdistan now, NE Iraq.