Refer to the https://www.warframe.com/news/cross-platform-save
Q: I did not create a PC account before the cutoff date. Can I still Merge multiple console accounts?
Yes, provided the console accounts you wish to include in the Merge were created before the cutoff date and also were not created through a previous PC-to-console account migration.
You will first need to create a new PC account. After that, you must Link it to whichever console account you are choosing as the Primary Account (allowing you to use its Progression). This will create a unified Warframe Cross Platform Save Account. You can then Merge the remaining console accounts with your newly created Cross Platform Save Account as you would normally.
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Even if your PC acc is created after the cutoff BUT your console acc is eligible to merge, you still can merge with that new created PC acc
If I am not understand the above wrongly or DE make changes on the rule....
But LINK...you will lost the PA on that PC acc.