#ESMin 2, 12 chars / 26 bytes (non-competitive) ïĪ(ᶐ+ɒ,ᶐᴙ+ɒᴙ [Try it here (Firefox only).][1]

Added transliterate function after the challenge was posted. #Explanation ïĪ(ᶐ+ɒ,ᶐᴙ+ɒᴙ // implicit: ï=input ïĪ( // transliterate ï... ᶐ+ɒ, // from uppercase+lowercase alphabet... ᶐᴙ+ɒᴙ // ... to reversed uppercase+reversed lowercase alphabet // implicit output [1]: http://molarmanful.github.io/ESMin/interpreter2.html?eval=false&input=Programming%20Puzzles%20%26%20Code%20Golf&code=%C3%AF%C4%AA%28%E1%B6%90%2B%E1%B6%9B%2C%E1%B6%90%E1%B4%99%2B%E1%B6%9B%E1%B4%99

ESMin 2, 12 chars / 26 bytes (non-competitive)

ïĪ(ᶐ+ɒ,ᶐᴙ+ɒᴙ

Try it here (Firefox only).

Added transliterate function after the challenge was posted.

Explanation

ïĪ(ᶐ+ɒ,ᶐᴙ+ɒᴙ // implicit: ï=input
ïĪ( // transliterate ï...
 ᶐ+ɒ, // from uppercase+lowercase alphabet...
 ᶐᴙ+ɒᴙ // ... to reversed uppercase+reversed lowercase alphabet
 // implicit output