Sandshrew locations — where to catch

In Kitakami (Scarlet & Violet – The Teal Mask)

• Paradise Barrens — Walk
• Reveler's Road — Walk

In Blueberry Academy (Scarlet & Violet – The Indigo Disk)

• Polar Biome — Walk

In Sinnoh (Diamond, Pearl & Platinum)

• Wayward Cave — Walk

In Johto & Kanto (HeartGold & SoulSilver)

• Goldenrod City — Gift
• Johto Safari Zone — Walk
• Mt. Moon — Walk
• Union Cave — Walk

In Hoenn (Ruby, Sapphire & Emerald)

• Mirage Tower — Walk
• Route 111 — Walk
• Route 113 — Walk

In Kanto (FireRed & LeafGreen)

• Route 10 — Walk
• Route 11 — Walk
• Route 23 — Walk
• Route 4 — Walk
• Route 8 — Walk
• Route 9 — Walk

In Johto & Kanto (Gold, Silver & Crystal)

• Mt. Moon — Walk
• Route 3 — Walk
• Route 4 — Walk
• Union Cave — Walk

In Kanto (Red, Blue & Yellow)

• Mt. Moon — Walk
• Route 10 — Walk
• Route 11 — Walk
• Route 23 — Walk
• Route 3 — Walk
• Route 4 — Walk
• Route 8 — Walk
• Route 9 — Walk

Other games (9)

• Brilliant Diamond / Shining Pearl (Gen 8): Kanto
• Sword / Shield — The Isle of Armor (Gen 8): Challenge Beach, Courageous Cavern, Warm-Up Tunnel
• Let's Go, Pikachu! / Let's Go, Eevee! (Gen 7): Celadon City, Kanto Route 3, Kanto Route 4
• Ultra Sun / Ultra Moon (Gen 7): Mount Lanakila, Tapu Village
• Sun / Moon (Gen 7): Mount Lanakila, Tapu Village
• Omega Ruby / Alpha Sapphire (Gen 6): Hoenn Route 111, Route 113
• X / Y (Gen 6): Friend Safari
• Black 2 / White 2 (Gen 5): Desert Resort, Relic Castle
• XD (Gen 3): Pokespot

Sandshrew — full Pokédex entry