普通に出来るけど

$ cat hoge.sh
echo "hoge.sh is called with $1"
if [ "$1" = "fuga.txt" ] ; then
fuga="fuga2.txt"
. ./hoge.sh $fuga
fi

$ . ./hoge.sh fuga.txt
hoge.sh is called with fuga.txt
hoge.sh is called with fuga2.txt