Need advise for relationshipType option archeType neutral or allied

[TorpedoA]

I am not familiar with this options at all. So please forgive my stupidity.
This is my scenario:
4 Factions (148 BC)

1. Roma (AI)
2. Hellas (player)
3. Celtica (player)
4. Germania (player)

Roma is at war with all the rest.
The 3 Anti-Roma factions (player) should neither be in a allied state (same alliance) nor at war with each other.

I only want to have the following conditions fullified:

A
I (player) want to be able to take over abandonded territories within the Anti-Roman factions.
(eg. Germania takes abandoned territory from Celtica)

B
I dont want to be able to move units within the Anti-Roman faction territories if units are present.
(eg. Germania units cannot help defend Celtica territories attacked by Roma)

C
I dont want to be able to help defend attacked territories by scramble within the Anti-Roman factions.
(very related to B?)

Questions

1. Does this make any sense at all?
2. Is realtionshipType archetype neutral the option of choice here?
3. What does the archeType neutral allow or not allow exactly?

I have a hard time to get my brain around that. Hopefully it doesnt sound totally stupid. I have a stressfull phase at the moment and my brain doesnt respond that well if am stressed. :brain:

[Cernel]

@torpedoa Are you sure you want to have a 1v1 game in the first place? This seems a game that, realistically, has to be more than two-sided (and arguably it should be a FFA). It not like there is something like "Roma" and everything else is fighting against it only.