The SM-CN900 Quick Link chain lock is compatible with 11-speed chains, making it suitable for your bike with 11 gears in the rear. It is designed to work with current 11-speed Shimano chains and allows tool-free installation. The number of chainrings at the front (2 in your case) does not affect compatibility, as this quick link is specifically for the chain's speed compatibility, which is 11-speed here.

10-speed chains are wider on the outside, not on the inside, so theoretically they are, but there are special chains for 10-speed .... I wouldn't try it and buy one for 10-speed. You also don't have to buy a new one every time you open it, I ride with a waxed chain and often take it off. I have already opened and closed the Powerlock 10 times without any problems

The item SMCN9000 is a Quick-Link chain lock is a set with 2 locks. This chain lock can be used for all Shimano 11 chains with Quick-Link lock. The TL-CN10 pliers are used for mounting and dismounting.