Will I get flagged for using too many of the same keywords?

Hi, So lets say I want to do a niche affiliate site on baseball. Say my website name is baseballguide.com. Naturally, I am going to have many articles with the word baseball. So I might write up to 10+ articles that I want to rank for, which goes like:

baseball hats
best baseball bats
baseball rules
baseball gloves
etc. etc.

Will I get red flagged for this? Considering that my domain already indicated clearly that I am a pure baseball niche sites?

seems all of these KWs are exact money keywords

No, this is fine. Your domain is not even exact match, nor partial match. The only keyword you are mentioning in the domain name is "baseball" and I really doubt that you can overdo it with a keyword "baseball" unless you really tried.

This is completely normal, go for it.

no yo can even make 1000 ages about the same kw ..... just look that you show google which page it the one you like to rank

Well you should be able to use keywords, and using the right keyword at the right density would point to the right resources, thus, if used in the right way, is actually a bonus to your site. If no keywords are used, then the search engine would probably identify that as a wrong resource, which may be bad for your ranking.
However, using well written an engaging content would be a bonus, as the search engines are pretty smart these days, as they have a metric that can measure the visitor's engagement on your site/content, and that would give your site authority in the process.