I'm pretty sure he'll go 3D.
May be something like Mario Odyssey or Sonic Frontiers (without the running fast thing though).
I like to imagine his games competing with the Zelda franchise while still being a platform game like Mario Odyssey or Sonic Frontiers.
I had ideas for an Alex Kidd game which serves as a reboot to the series. One of my ideas to contribute to Alex Kidd would be the Bladecore and Fancore as alternates to
Shellcore. Gooseka, Chokkinna, and Parplin would be recast as allies and teachers to Alex who teach these various core techniques. The core techniques are used in combat as well as some puzzle solving that follow the rock-paper-scissors relations.
I even came up with this in-game card game that also use rock-paper-scissors relations to play. The idea was various towns had saloons where Janken's loyalists hang out and Alex could go in and play cards with them. This card game was to replace the regular rock-paper-scissors matches.
When Miracle World DX came out, I decided to forget the idea given no point in a reboot now that we have a remake, but I might reuse the rock-paper-scissors card game idea somewhen along the line.