It was previously reported that WWE had interest in signing Lucha Underground and Impact Wrestling stars Rey Fénix & Pentagón Jr., but they are reportedly signed to contracts with the Lucha Underground promotion for the foreseeable future.
According to a report from PWInsider.com, they are indeed signed with Lucha Underground until 2020, which means that they will have to honor their contracts with LU until then, assuming that the show is still on the air at that time.
They are reportedly in negotiations with Impact Wrestling about signing new deals with Impact, and they have also signed on to stay with Major League Wrestling until the end of 2019, according to Court Bauer. So it would appear as though they won't be heading to WWE for a while, if ever.
I've moved heaven and earth. Penta, Fenix and Salina are with MLW for the foreseeable future. Salina just signed a new deal and the Lucha Bros are committed through end of 2019 at the very least. 🎂 https://t.co/NhD5rKRO4u— Court Bauer (@courtbauer) September 18, 2018