Yes. The correct model BlackHawk T-series L2D Duty Holsters for a Glock 19 with a TLR-8 equipped are MPN:44NE00BKR (Right Hand/Plain), MPN:44N300BWR (Right Hand/Basketweave), MPN:44N300BWL (Left Hand/Basketweave), and MPN:44NE00BKL (Left Hand/Plain).
The BlackHawk T-series L2D Duty Holster could be used with a TLR-1 and RMR depending on what gun and model holster you are asking about.
The BlackHawk T-series L2D Duty Holster will not accommodate a Glock 20 with an optic equipped. I would recommend using the PHLster Floodlight OWB Belt Holster, which will accommodate your light and optic, and can be found by using the link below:
https://www.opticsplanet.com/phlster-floodlight-owb-belt-holsters.html?_iv_parent-gun-make=glock&_iv_parent-gun-model=glock-20&_iv_holster-type=outside-the-waistband-holster&_iv_light-laser-attachment=streamlight-tlr-1
This BlackHawk T-series L2D Duty Holster will not fit your M&P 2.0. I would recommend the Safariland 7280 Mid Ride Duty Holster or the Safariland 7TS ALS Mid Ride Duty Holster found using the following links:
https://www.opticsplanet.com/safariland-7280-mid-ride-duty-holster.html?_iv_gun-model=smith-and-wesson-m-and-p-9-4-dot-25in
https://www.opticsplanet.com/safariland-model-7390-7ts-als-mid-ride-duty-holster-safa-7390.html?_iv_gun-model=smith-and-wesson-m-and-p-9-m2-dot-0&_iv_barrel-length=4-dot-25-in
Yes, MPN: 44N213BKR will be compatible with the TLR-1/2 HL.
There are models of the T Series holster that are made for Staccato pistols and will fit all 3.9”, 4.15”, 4.4”, 5” and 5” compensated duty guns (Omni, DVC-P, Staccato-XC) with mounted light. However, this version of the T Series is only available exclusively through Staccato's website. You can find this holster here: https://staccato2011.com/products/staccato-2011-t-series-l3-duty-holster-by-blackhawk-holsters/
Yes, the T-Series holster will fit the Staccato P pistols.