Without the inversion: the godparents/sponsors and baptising minister incur impediments of spiritual relationship with the baptised person. In other words, according to canon law, they can't marry.

In English you incur an impediment.

"The only spiritual relationship that annuls marriage is that mentioned in can. 768.
It arises only from Baptism and exists between the baptizing minister and the baptized person and the baptized person and the sponsor. Therefore no valid marriage can be contracted:
1. Between the baptizing minister and the baptized person;
2. Between the sponsor and the baptized person."
http://catholicharboroffaithandmorals.com/Impediment Spiritu...

"Question 56. The impediment of spiritual relationship"
http://www.newadvent.org/summa/5056.htm

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Note added at 1 hr (2015-05-08 15:45:11 GMT)
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"I was honored to be asked to be the baby's godfather, but I did not know if that was permitted. A canon lawyer told me that I would incur an impediment against marrying Erica in the future. After a quick calculation of the age difference between us, I decided it was a risk I was willing to take."
https://books.google.es/books?id=8qJJ7iwByMgC&pg=PA12&lpg=PA...

This is a may be situation of which i am not sure. The best I could try is nearly literal translation.