Hey.
So just to preface this, I don't own any of the masks you list above apart from the MF1A.
First to address the best option (imo) in your list. I figure the FMJ08 would be your best option. It from my knowledge is used today by the Army of China, and therefore should have vetting for its design and such. I haven't heard of the Delta-Plus rotor Galaxy m9200/m9300. However, I would not discount their designs, I would look for what their masks are certified for.
However, I do NOT recommend using the MF1A. It may only be my experience, but out of all my collecting of surplus equipment, my recent production MF1A was the only which had an exhale valve issue. In addition, again in my experience, but the rubber is far stickier and tends to pull a lot more on hair than my Russian ShMs.
Next point, NATO and STANAG are the same thing afaik. NATO would refer to the STANAG 4155 standard which dictates thread connections. Make sure the filters you get can thread into the mask you get, because from China in my experience they seemingly use mostly GOST, but there are companies which use NATO, so you have to be careful. NATO filters will not thread into a GOST mask (The GOST thread is slightly too thin and the pitch is off). GOST filters should thread into a NATO mask (this is due to the NATO thread being wider). The pitch is still off though, so I don't recommend this, because if for whatever reason (extremes of tolerances for example), their widths become too similar, the pitch will screw it up and they will not thread. So imo just stick with what the mask expects. NATO if NATO, GOST if GOST.
The 3M adapter is NATO fyi, so plan accordingly. Also, you may be better off using 40mm particle (P3) filters, as the gasket is quite flimsy and could be damaged. In addition, the adapter may not thread into every mask, due to the lugs which you use to screw it in may get in the way. Here's a video going over the basic issues: https://www.youtube.com/watch?v=-Vy8x0Z5sD4&t=26s
I cannot speak to how well N95 filters work. I have heard they are enough, but I am not totally sure.
My assumption is that you want particle filters mainly. If you want a filter for other threats, then I'd recommend a NBC rated filters (these tend to be hard to find though).
For particulate threats, P3 should be the protection you want on ABEKP filters (it is the highest you can get). I don't know if P2 (I don't think P1 would) would work, so to be safe I would recommend P3.
In terms of cheap filters, I would recommend in date filters, but if none are available, you can purchase expired combined filters which include P3, which as an example (expired in 2012): https://www.ebay.com/itm/4-bulk-filters-gas-mask-filter-40mm-replacement-gas-mask-filters-bulk/263207696760?hash=item3d4866b978:g:AaMAAOSwEZdaSNc6