The rumored reason that we haven't seen much of Asuka on SmackDown Live for the past couple of months is that WWE creative has nothing for her.
When Asuka was signed to WWE back in 2015, she was quite rightly portrayed as a huge and extremely important acquisition. As most of you likely know by now, during her entire two year run in NXT The Empress didn't lose a single match. In fact, when it came to her moving on to Raw, Asuka had to relinquish the NXT Women's Title since no one had been able to take it from her.
Once Asuka got established on Raw, normal service resumed for a little while. Not only did WWE refuse to have her lose in singles matches, but she didn't lose at all. The Empress Of Tomorrow won the first ever women's Royal Rumble match and also the first ever Mixed Match Challenge alongside The Miz. Then came her Women's Championship match versus Charlotte Flair at WrestleMania 34, and that's where her undefeated streak came to an end.
Since then it would be fair to say that Asuka has lost her shine, especially in the eyes of WWE. Between WrestleMania and now, all The Empress has had is a rivalry with Carmella, during which she lost back-to-back PPV matches. After that feud came to an end Asuka all but disappeared, not returning to television again until last week when she came to the ring to help out Naomi.
The sad fact of the matter is that according to The Wrestling Observer, WWE's creative team simply has nothing for her. How you can have nothing for someone that talented is anyone's guess. Bryan Alvarez spoke about Asuka on Wrestling Observer Live, reporting that WWE had originally planned to turn The Empress heel but had a change of heart and filled that slot with Becky Lynch instead.
On the bright side, Asuka is at least going to be back on SmackDown Live for the next few weeks. The Empress is booked to team with Naomi at WWE Super Show-Down to take on The Iiconics. She will also be defending her MMC crown with The Miz again when the tournament returns later this month. Beyond that though, who knows what's in store for Asuka? Hopefully a title run since she is yet to be a champion on the main roster.