What will happen to unlcked squads?

lets say i havent unlocked last 5 squads at normandy allies.
Will i be able to unlock them with xp after merge or they will remove them permanently ?

I’m going to answer this as if it was two questions as I’m not quite sure what you’re asking.

1: Will squads I unlock stay unlock?
Yes, You will keep all squads and be able to upgrade them, Their upgrades also effect squad members of the same type, got level 3 assulters and they’re maxed? then all level 3 assulters are coming maxed.

2: Will squads I failed to unlock be able to be unlocked.
This is a weird answer but: Yes and no.

What I mean by this: You will have the XP and such you have placed in that squad (let’s say you had 90% of it done, then it will be 90% done post merge.) but it will probably not be the same squad, It will be a different squad or be a weapon used by a different squad.

If some of them are available as squads in the tech tree - Yes
If no, you won’t be able to unlock them, because there is no point to put 6 of the same squad type in the tech tree.
To the question in the topic name - Unlocked squads stay yours.