Emoji Keyboard is described as 'This is a freeware software that supports near thousand popular emojis. You can put them in any text field while chatting, posting or commenting'. There are four alternatives to Emoji Keyboard for Windows and PortableApps.com. The best alternative is BabelMap, which is free. Other great apps like Emoji Keyboard are WinCompose (Free, Open Source), SymbSearch (Free, Open Source) and winMoji (Free, Open Source).
BabelMap is a free character map application for Windows that allows you to browse through the entire Unicode character repertoire of over 107,000 characters, or search for a particular character by name or by code point.