AJX's fleet is comprised of ANA airplanes. We do not have our own aircraft. We use ANA planes to fly the flights that ANA gives to us. There are only four flights that we use the Air Japan call sign on, to/from Incheon and to/from Singapore. All others we use All Nippon. The latest that I have heard is that we are losing flights due to not having enough pilots to fly them. The BKK passenger flight is one example.
As far as Europeans that are here, I know of at least one Italian and another pilot that lives in Italy. Various other nationalities from Europe as well.
To address which agency is the best, I have no idea. I am US based and am through Crew. I have no major complaints with them now that I am working there. During the application process I have heard of some people waiting for long periods of time to hear from them. I get paid on time every time and the pay is correct. When I email the office I get an answer within a day. When my wife had to get ahold of me in an emergency they went out of their way to help her. So no real complaints from me regarding Crew.