With FTG restricted and MS restricted, Itachi wins. Minato already explained that SM isn't his forte due to how long it takes him to gather NE and he isn't able to maintain it for very long. If he's by himself with no support, he won't have a chance to gather it since he'll be focused on the fight itself.
Summonings are the worst thing he could do since Itachi could place them under his control. Ma and Pa for an infinite SM? If he were able to do it, he would've used it more often in the past but instead he said that he rarely used it in the past because of how inefficient it is (takes too long and lasts too little). This implies that merging with Ma and Pa is not something he has done. I won't give him that feat.
Itachi wins.
Summonings are the worst thing he could do since Itachi could place them under his control. Ma and Pa for an infinite SM? If he were able to do it, he would've used it more often in the past but instead he said that he rarely used it in the past because of how inefficient it is (takes too long and lasts too little). This implies that merging with Ma and Pa is not something he has done. I won't give him that feat.
Itachi wins.