OP/TECH USA D-Pro Zoom SLR Digital D-Series Soft Pouch (Black)

Depending on the lens pairing, you would either use the OP/TECH D-Pro-Zoom or D-Pro-Tel SLR Digital D-Series Soft Pouch with the Nikon D6 Mirrorless Camera.

To fit the Canon EOS R5 Mark II Mirrorless Camera with the Canon RF 24-70mm f/2.8 L IS USM Lens or the Canon RF 70-200mm f/2.8 L IS USM Lens attached, I would recommend the OP/TECH USA D-Pro Tele Digital D-Series Soft Pouch (Black) instead: BH #OPDDPROTPB.

The D-Pro Zoom is a good choice for your camera/lens combination if you have a battery pack on the bottom of your camera. Fits: 6" x 6.5" x 8" (15,2cm x 16,5cm x 20,3cm) If you do not have a battery pack, the D-SLR Zoom may be a better fit (more snug). Fits: 6" x 4.5" x 8" (15,2cm x 11,4cm x 20,3cm) Width x Height x Depth (Depth is measured from the back of the camera to the end of the lens.) https://www.bhphotovideo.com/c/product/340285-REG/OP_TECH_USA_7401204_Digital_D_Soft_Pouch.html

If you want a pouch for the body only (no lens) and do not have a battery grip on the bottom of your camera the Body Cover Auto, stock # 8201004, fits 6" x 4.5" x 3" (15,2cm x 11,4cm x 7,6cm) (body width, height, and depth) would be a good choice. For the body only with a battery grip, the Body Cover AF-Pro, stock # 8201054 fits 6" x 6.5" x 3" (15,2cm x 16,5cm x 7,6cm). The D-Pro fits 6" x 6.5" x 6" (15,2cm x 16,5cm x 15,2cm) so if you have a battery grip on your camera and a shorter lens, this should fit. If you do not have a battery grip, the best sizes are the D-SLR, D-SLR Zoom, or D-SLR Tele, depending on which lens you have. D-SLR # 7401094 fits 6" x 4.5" x 6" (15,2cm x 11,4cm x 15,2cm), D-SLR Zoom #7401204 fits 6" x 4.5" x 8" (15,2cm x 11,4cm x 20,3cm), and D-SLR Tele #7401234 fits 6" x 4.5" x 11" (15,2cm x 11,4cm x 27,9cm). If you’ve added any additional hardware to your camera (i.e. lens hoods, brackets, filters, longer lenses, etc.), it may affect the fit so it is always best to measure to insure that you will get the best fit.

The answer would depend on which 300mm you are considering. If you already have the Canon 80D with a 300mm + 1.3x extender, measure the combination. If those numbers are 1/2 less than the pouch's exterior dimensions of 6.0 x 6.5 x 11.0 (15.2 x 16.5 x 27.9 cm) we feel you are good to go.

Thanks for your question. The Nikon Z7 actually fits in our D-Midsize pouch; however, your lens is too big to fit in this case. We don't make any cases to fit a lens of that size when attached to the camera. We do offer lens pouches when storing the lens separately (Snoot Boot) and you could have your camera body stored in our Soft Pouch-Body Cover-Midsize or Midsize-Pro if you have the extended battery grip. I'm sorry that we don't manufacture exactly what you're looking for. Cheers!

While this case can fit the Sony A7R II body, it will not fit with a Sony FE 24-70mm GM Lens attached to it.

Yes, the OP/TECH USA D-Pro Tele Digital D-Series Soft Pouch (Black) is large enough to fit a Canon R6 with a Canon RF 100-400mm f/5.6-8 IS USM Lens.