43 cards where the text includes “planeswalker” and it’s legal in Standard and the rarity is less than or equal to uncommon

Angelic Intervention (March of the Machine #5)
Animist's Might (March of the Machine: The Aftermath #20)
Annihilating Glare (Phyrexia: All Will Be One #80)
Bite Down (Dominaria United #155)
Bitter Triumph (The Lost Caverns of Ixalan #91)
Blot Out (March of the Machine: The Aftermath #12)
Calamitous Cave-In (The Lost Caverns of Ixalan #139)
Charge of the Mites (Phyrexia: All Will Be One #6)
Citizen's Arrest (Dominaria United #11)
Cosmic Hunger (March of the Machine #182)
Cut Short (March of the Machine #10)
Deadly Derision (March of the Machine #99)
Extinguish the Light (Dominaria United #94)
Feed the Cycle (Bloomburrow #94)
Fires of Victory (Dominaria United #123)
Hard-Hitting Question (Murders at Karlov Manor #164)
Hurloon Battle Hymn (Dominaria United #131)
Invasion of Azgol // Ashen Reaper (March of the Machine #232)
Invasion of Azgol // Ashen Reaper (March of the Machine #232)
Jaya's Firenado (Dominaria United #134)
Lithomantic Barrage (March of the Machine #152)
Long Goodbye (Murders at Karlov Manor #92)
Molten Rebuke (Phyrexia: All Will Be One #141)
Obliterating Bolt (The Brothers' War #145)
Ossification (Phyrexia: All Will Be One #26)
Overwhelming Remorse (The Brothers' War #110)
Planar Disruption (Phyrexia: All Will Be One #28)
Powerstone Fracture (The Brothers' War #112)
Rebel Salvo (Phyrexia: All Will Be One #144)
Repair and Recharge (The Brothers' War #24)
Rona's Vortex (Dominaria United #63)
Scorching Dragonfire (Duskmourn: House of Horror #156)
Serum-Core Chimera (Phyrexia: All Will Be One #215)
Shatter the Source (March of the Machine #164)
Sheoldred's Edict (Phyrexia: All Will Be One #108)
Stonesplitter Bolt (Wilds of Eldraine #151)
Take Out the Trash (Bloomburrow #156)
Tandem Takedown (March of the Machine #208)
Torch the Tower (Wilds of Eldraine #153)
Unleash Shell (The Brothers' War #155)
Vivisection Evangelist (Phyrexia: All Will Be One #220)
Volcanic Spite (March of the Machine #170)
Vraska's Fall (Phyrexia: All Will Be One #116)
Yotia Declares War (Dominaria United #153)

The message was clear to Sorin—time to search for something else.