I always use HTML editor mode to writing each of my post, and below are the list of the shortcuts that I use.

Blockquote : Alt + SHIFT + q
Bold : Alt + SHIFT + b
Code : Alt + SHIFT + c
Insert date/time : Alt + SHIFT + s
Insert IMG URL : ALT-SHIFT-m
Italics : Alt + SHIFT + i
Line Break : SHIFT + Enter
Link : Alt + SHIFT + a
List Item (li) : Alt + SHIFT + l
Ordered List (ol) : Alt + SHIFT + o
Publish the Post : Alt + SHIFT + p
Read More : Alt + SHIFT + t
Redo : CTRL + y
Strikethrough : Alt + SHIFT + d
Undo : CTRL + z
Unordered List (ul) : Alt + SHIFT + u

Have I missed out something ? If that’s the case please let me know using the comment section.

Hope this helps.