This should be no problem. First you need my macro file from the ultimate word definitions sorting macro. Load this macro file and add the following macro to this macro file with name "AddFunctions" for example. AddFunctions needs also macro property Continue if a Find with Replace not found set and disable also the Cancel dialog for your macro.

The code for your macro follows. It contains 2 colored strings which you have to adapt to your environment.

The macro first collects in clipboard 9 all function strings in the current file.
Then it pastes it to a new file and if this new file contains really characters (functions found), it's content is reformatted with a single regex replace to get 1 function name per line. This list of function names is again copied to clipboard 9 and the new file is closed without saving.

Next your wordfile is opened and with a single Find the cursor is set to the color group of your functions. The name of this color group should be unique in your wordfile or you have to use more finds to get to correct position. Below this line the function names are inserted into the wordfile.

The real hard work is done by my macro SortLanguage set. Last your macro has only to save the wordfile and close it. SortLanguage has restored already the standard editing environment (clipboard 9 cleared, switch to Windows clipboard, ...).

InsertMode
ColumnModeOff
HexOff
UnixReOff
Top
Clipboard 9
ClearClipboard
Loop
Find RegExp "def[ ^t]+*[ ^t]+{"
IfFound
CopyAppend
Else
ExitLoop
EndIf
EndLoop
NewFile
UnicodeToASCII
UnixMacToDos
Paste
IfColNum 1
ClearClipboard
Clipboard 0
ExitMacro
EndIf
Find RegExp "def[ ^t]+^(*^)[ ^t]+{"
Replace All "^1^p"
SelectAll
Cut
CloseFile NoSave
Open "Name of your wordfile with full path"
Find "/C7"My Functions""
EndSelect
Key HOME
Key DOWN ARROW
Paste
Key UP ARROW
PlayMacro 1 "SortLanguage"
CloseFile Save

Add UnixReOn or PerlReOn (v12+ of UE) at the end of the macro and before the single ExitMacro command if you do not use UltraEdit style regular expressions by default - see search configuration. Macro command UnixReOff sets the regular expression option to UltraEdit style.

Hope this macro really works because I have not tested it. I have written it directly here in the forum edit box.

If you are brave and have time you can adapt this macro and replace the macro SortLanguage call by selecting all words of the color group of your functions only and use the appropriate code sequences from my macro set to sort only the words in this color group. This would speed up the execution of your macro.