I have found there is a load of extra fake Japanese players which are free agents but don't appear in the free agents list but have not been discarded, a lot with real faces. Many are duplicates of existing players or what seems to be older versions. Some are individuals that require a name change. I got most of them real names from PESmaster, Though a few I had to find out who they were using transfermarkt.com and the likes.
What you can do to edit them is swap them in through National team selection temporarily.. then edit then return the originals back into the squad. I have made a guide of sorts.
The guide follows this pattern
fake name (REAL NAME) > Temp. Switch Player
ochiai (nosono) > E. Kawashima
K. Okawara (Hosogai) > G. Shoji
R. Murase (K. Kawamata) > Uchida
I. Haneda (Yuji Rokutan) > G. Sakai
K. Onoguchi (H. Sakai) > Y. Konno
S. Terada (R. Morioka) > Aoyama
S. Ota (Yu Kobayashi) > K. Honda
^^Not to be confused wirth (Kobayashi, Yusuke) [MENTION=185924]kash[/MENTION]iwa Reysol
H. Chiba (NAOYUKI FUJITA) > T. Inui
K. Harada (WATARU ENDO) > Kagawa
S. Kinoshita (TAKUMA ASANO) > S. Okazaki
K. Matsuo (Haraguchi) > S. Nishikawa
H. Kamishima (T. Taguchi) > Gonda
K. Ohira (TAKUJI YONEMOTO) > M. Yoshida
H. Shiozawa (Osako) > Shiotani
K. Hamaguchi (G. Sakai) > Morishiga
I. Kodama (Yamaguchi) > Y. Nagatomo
R. Asai (SHOGO TANIGUCHI) > Ota
R. Tanimura (K. Nagai) > Hasebe
Those are the ones which you can edit. The following are doublers and should remain with there fake names or be used as bases for edits.
fake name (Real name) > Team where there double resides.
Y. Makino (D. Nishi) Doubler - Kashima Antler
M. Furuhata (T. Usami) Doubler - Gamba Osaka
A. Sugita (M. Higashiguchi) Doubler - Gamba Osaka
H. Takayanagi (N. Ueda) Doubler - Kashima Antler
R. Hirao (K. Matsubara) > Doubler - National team
N. Wakita (H. Fujiharu) Doubler - Gamba Osaka
Y. Tejima (G. Shibasaki) Doubler - Kashima Antler
R. Hisakawa (G. Shoji) Doubler - Kashima Antler
I. Ozawa (Y.Muto) Doubler - Urawa R D
M. Oikawa (J. Tanaka) Doubler - Sporting
R. Kurokawa (D. Niwa) Doubler - Gamba Osaka
Y. Iwanaga (S. Koroki) Doubler - Urawa R D
M. Takimoto (Okazaki) Doubler - Leicester City
Y. Mihara (S. Nishikawa) Doubler - Urawa R D
R. Omura (Havenaar) Doubler - Ado Den Haag
S. Furuta (T. Makino) Doubler - Urawa R D
A. Sone (Y. Kakitani) Doubler - FC Basel
A. Kuno (M. Yoshida) Double - Southampton
R. Fujisawa (Inui) Doubler - SD Eibar
H. TSUCHIDA (K. Yonekura) Doubler - Gamba Osaka
R. Ise (S.Kurata) Doubler - Gamba
K. Iizuka (Y.Nagatomo) Doubler - Inter
H. Fukada (D. Suzuki) Doubler - Kashiwa Reysol
Okay, hope that makes sense and is somewhat helpful.