For a Springfield XD(M) Elite 10mm with a Trijicon red dot mounted, you would need the Warden Chest Holster in size 2RDO, which fits size 2 frame pistols equipped with a red dot optic.
For a Glock 21 with a red dot optic (such as a Crimson Trace) you would want the Size 2RDO version of the Warden holster. The Streamlight mounted under the barrel does not change the size selection, since the wrap-style holster is designed to accommodate a light or laser on any size without needing a different size.
For the S&W M&P 2.0 Performance Center in 10mm, you would want Size 2, since it is designed for mid and full-sized pistols like the S&W M&P series.
The P89 would fit in size 2.
The Elite Survival Systems Warden Chest Platform Holster size 3 should work with that revolver.
The Elite Survival Systems Warden Chest Platform Holsters size 2 should fit that gun. However, the holster will not fit the gun properly with a red dot mounted.
The Elite Survival Systems Warden Chest Platform Holster size #3 will be compatible with a Taurus Judge.
The Elite Survival Systems Warden Chest Platform Holster size #2 will be compatible with your Glock 40.
The correct size Elite Survival Systems Warden Chest Platform Holster for an M&P Shield EZ in 9mm is Size #1.
The Elite Survival Systems Warden Chest Platform Holsters size 1 should work with the S&W M&P Shield EZ.