You could do it like this using a couple of maps sandwiching a sort.

$ perl -le '
> @arr = qw{ TEXT1 TEXT3 TEXT11 TEXT2 TEXT13 };
> print for
>    map  { $_->[ 0 ] }
>    sort { $a->[ 1 ] <=> $b->[ 1 ] }
>    map  { [ $_, ( split m{(?<=[A-Z])(?=\d)} )[ 1 ] ] }
>    @arr;'
TEXT1
TEXT2
TEXT3
TEXT11
TEXT13
$
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I hope this is helpful.