Original Japanese emoji resources
Note that starting in April 2012, E-Mobile and KDDI au basically adopted NTT Docomo's i-mode emoji design, while SoftBank kept their own design which was already relatively close to NTT Docomo.
Sharp (and Canon) electronic typewriters had monochrome emojis in private-use (Shift) JIS positions. These got reused for [J-Phone]'s and thus later Vodafone's and Softbank's original emojis that competed with NTT Docomo's.
Until circa mid-2015, Japanese carriers added emojis in their traditional design to Android phones, just like Samsung still does and LG and HTC used to do.
Disney Mobile was a brand of Softbank. Its emoji set only changes some glyphs.
Y! Mobile, the Yahoo-based brand under the SoftBank umbrella, fuses the prior Willcom and E-Mobile services. Willcom was a PTT (or PHS) provider, a non-cellular mobile phone technology almost only used in Japan.
KDDI uses au as a brand name. It previously used labels like EZweb and TUKA. They got their graphics mostly from Openwave who provided the mobile WAP browser.
E-Mobile had a service known as eAccess.
Astel was another local PHS provider with early, monochrome emoji support.
Also see this Google Spreadsheet for codes etc.
The original Unicode mapping tables etc. were hosted at Google Code, but were moved to Github (E4U) when Google Code was closed down. The documentation is still found at a Google Site. Official Unicode documentation now has full chart (huge document) and a table of emoji origins of particular interest for this project. The latest raw data also includes a machine-readable file that is basically the condensed result of the E4U work.
- suzukitakafumi/emojicodecs: Codecs for mobile japanese mobile phones (DoCoMo, KDDI, SoftBank extended Shift-JIS and UTF-8 PUA)
- wakaba/hatena-emoji-data: Hatena emoji convertion table and scripts
Other messaging platform emojis
Even less so than early 2000s competing Japanese telecommunication providers, many vendors of instant messengers and chat apps do still not seem interested in adopting Unicode as the sole method to interchange emojis. They keep custom sets, some of which can easily subsumed under the Unicode repertoire, others cannot. Some of these software products are already obsolete. The Unicode Consortium may consider these existing emojis, but often they ignore or alter this prior art when standardizing new emojis, because it is not a matter of interoperability. Some of these allowed theme packs or skins to alter the looks of their emojis.
This includes AIM and ICQ, Skype and Windows/Microsoft (Live) Messenger, GTalk, Viber, WeChat and [QQ], Yahoo! Messenger, Blackberry Messenger (BBM) and Cisco, FOSS Trillian and Pidgin, but also forum and blog software like phpBB and Wordpress. Furthermore, some online games (often MMORPG) feature custom emoji sets for in-game communication, e.g. Furcadia.