it's function avaible with adminmod and converted to use with amx.
tape messagemode on your console
after tape on console amx_messagemode <AMX FUNCTION>
and say <variable>.
amx_nomessagemode
Exemple :
messagemode (optionnal but more easy)
amx_messagemode amx_slay
if you say
"Player"
the player is slayed
after if you say
"Taz-devil" taz-devil is slayed
amx_nomessagemode to deactivate
you can do this with all amx command.
If you want to see all your "say" with amx_tsay format and green color.
Bind sample:
bind "z" "amx_messagemode amx_tsay green;messagemode"
bind "x" "amx_nomessagemode"