In Romanian there are 2 words, which are related:
There is the less common word, very similar to other Romance languages already mentioned consocri where socri means "parents-in-law" and there is also cuscri, which is just the shortening of consocri.
Cuscri is the common and proper word in modern Romanian.
All the above are plural unknown/male gender form. The other forms are:
cuscru - singular male
cuscră - singular female
cuscre - plural female
cuscri - plural male or unknown gender
There are also derivatives of this word, such as:
încuscrire - to enter into such a relationship
Edit: After checking authoritative sources, I couldn't find any mention of consocru. So, I am either imagining it, or I might have heard it, but as a neologism due to recent Romanian massive migration to Italy/Spain and back.