Yes, you can put a 20mm strap on a 19mm lug width watch and a 22mm strap on a 21mm lug watch
Crossbody Leather Strap - 1 inch Wide - Modern Leather Colors – Mautto
Adjustable Crossbody Bag Strap - Choose Leather Color - 55 Maximum Length, 1/2 Wide, #19 Clips, Replacement Purse Straps & Handbag Accessories - Leather, Chain & more
Wide Crossbody / Messenger Bag Strap 50 Inch Length 1.5
Find Your Perfect Match: Customized Crossbody Purse Straps – Mautto
A How-to Guide for Choosing Your Cross Body Strap Length – Mautto
Leather Purse Strap Extender - 1/2 (half-inch) Wide - Nickel #13 Hook - Choose Color & Length, Replacement Purse Straps & Handbag Accessories - Leather, Chain & more
How to: Measure your wrist size and determine what length of strap you need.
Classic GOLD Chain Bag Strap With Leather Weaved/threaded
Watch Strap Sizing Explained [2022 Guide] • The Slender Wrist