Translation:That is not a matter to be easily agreed upon.
Matter, question, and issue all have distinct meanings but people, especially young people, tend to use "issue" for all three. Matter = the case under consideration. Issue = a matter in dispute needing resolution. Question = a matter requiring clarifcation or response. I'm not able to say which is closest to the meaning here, but don't expect the answer from DL.
dealt with and agreed upon. The previous sentence interpreted one way and this another with thoả thuận. More of a guessing game than an educational opportunity. The drop downs in this course would be best be eliminated so we could rely on outside sources for meanings rather than playing guessing games.