No. The mechanics are tied to what is calculated to happen during a Day cycle. So even if you could save freely, the game would roll-back to the start of the last saved day.
Hi, with "Unlimited item" you can create infinite "Qubit Chip", which let you level up you QC more that it should, so you can have more than 6 Alter.
Just so you know you can't finish the game with this, because Spoiler
you can only create 1 "Ark Sarcophagus" which lead to you not being able to say goodbye to 3 Alter, softblocking you. So if someone know a way to create more than 1 "Ark sarcophagus, please let me know.
The maximum number of Alters is 7 (after Act 2 and getting back the rebels). That is if you follow the story, do side quests and don't fuck shit up with cheats. I said goodbye to 7 Alters.