I doubt it considering the just spent a nice chunk of cash on Viv labs for their newest A.I. assistant tech and have will be including their own assistant named Bixby.
You likely will be able to access Google Assistant by some means but it almost certainly won't be front and center.
''A few new smartphones will be incorporating Google Assistant from the get-go as well, like the LG G6 and some other "newly announced partner devices." Sony, Huawei, Samsung, and HTC are all listed as companies with Android smartphones that will support Google Assistant''