There’s been no indication of that in the WoW: What’s Next talk, nor the WoW Deep Dive talk at Blizzcon.
The Shop Page still says that character transfers are not allowed between Classic and Retail, and there were a LOT of Shop changes (mostly related to new expansion for Retail) that dropped on Day 1 of Blizzcon.
I would not get your hopes up, as it seems very, very unlikely to me, but never say never.