Psychic powers are moving, there will be no psychic phase. Instead buffs/debuffs will be in the command phase, attacks will be in the shooting phase, and maybe other stuff will be abilities on the dataslate.
In general they are trying to remove the rules bloat where armies could have a multitude of rules from obscure releases and you can make a misplay cause you don't memorize each factions 30-50 stratagems.
Each faction will have all their Faction Tactics, stratagems, Warlord Traits, and Relics on a single sheet. Every faction will have only 6 stratagems and universal ones will be expanded. A lot of minor stuff will be shifted to each units dataslate.
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That's the 10th Edition Termagant dataslate. Some changes, each weapon has it's own strength and ballistic skill. We don't know how leadership works but probably succeeds on an 8+ from a 2d6? OC is objective controlled, and how much each unit is worth for holding a control point. Also the ability Skulking Horrors is an example of something that might of been a stratagem that is now an ability of the unit, allowing it to fall back from a potential charge.
I think the whole idea is to make it easier for you opponent to see all the abilities you have, being able to look at your dataslates and faction sheet and know all the tools you have in a fight instead of it being spread amongst several books.