bind alt + . in bash vi mode

I set it to emacs
set -o emacs
then i saw the function i was looking for was yank-last-arg
"\e.": yank-last-arg
"\e_": yank-last-arg

I tried to create it for vi mode with
set -o vi
bind -m vi-insert "\e.": yank-last-arg

but it does not work... as a side effect 'a' key stopped working :/

Does anybody knows how to achieve this?

Thanks!