This is called backshifting. When we use indirect speech, we often put the contents of the speech further in the past.
Let's first take a direct speech sentence:
Lekon Chekon said: "People who were brave enough to fight in WW2 should serve as examples to us".
Now let's report what Lekon Chekon said, and backshift the tenses he used:
Lekon Chekon said that people who had been brave enough to fight in WW2 should serve as examples to us.
This sentence employs indirect speech (no quotation marks). We backshifted were to had been.
Thus, your first sentence is correct. Note that even in the direct speech sentence we can use have been only if Lekon Chekon's words were pronounced during WW2:
In 2015, Lekon Chekon said: "People who have been brave enough to fight in WW2 should serve as examples to us". (WRONG: WW2 ended a long time ago)
In 1942, Lekon Chekon said: "People who have been brave enough to fight in WW2 should serve as examples to us". (RIGHT: WW2 is still going on)
If someone asked me, "how long have you played this game?", I would take it to be asking about the amount of time since I started playing - i.e. if I started playing a year ago, I would reply, "about a year".
I would say the same thing if someone asked me, "how long have you been playing this game?" The verb tenses "played" and "been playing" are different -- but "been playing" means that the playing is still going on, which is definitely the case if you're asking inside the game.
For example, I played Quake 3 for 2 years. Since I'm no longer playing Quake 3, "how long have you been playing" isn't appropriate - "played" is the better verb tense because the action concluded in the past.
None of this has any bearing on the current round. In my opinion, the better way to ask that question is to change the noun, not change the verb tense. For example:
How long has this round been going on?
^^ This means that the round is still ongoing.
How long was that round?
^^ This means the round has ended.
Best Answer
I agree with Vic, and would like to add a little more information.
The main point of the question is the difference between the tenses of "have been playing" and "have played". In addition to the tenses, we have the verb "play (tennis)", which is a dynamic verb (dynamic verbs have duration; they occur over time), and we also have the time phrase "for five years".
Different combinations of verb, tense, and time phrase will allow different ranges of possible readings.
Let's consider the first sentence:
The tense is the perfect progressive tense. The time phrase indicates the duration (five years). The combination of the tense and the time phrase forces us to read it as: "I have been playing tennis for five years now." This gives us the reading that the activity has been going on for five years up until now. It also implies that the activity will keep continuing, at least in the immediate future.
The tense is the simple perfect tense. The time phrase is, again, for five years. However, the sentence is different from (1). It doesn't force us to read the time part as "for five years now". It's unclear exactly when in the past that the speaker have played tennis. All we know is it happened before now, at least five years before now. (In other words, it's possible to read the sentence as "At some point in my life, I've played tennis for five years.") It's unclear whether it has ended or not. It's also possible that it's been continued up until now, and possibly will continue into the future. The speaker says nothing explicitly, so we have a wider range of possible readings.
Having said that, the preferred reading, out of context, is: "I have played tennis for five years now." Which means about the same thing as (1). When we read both alternatives as "for five years now", the difference is really small. To demonstrate such a small difference, these examples can be helpful:
I hope this helps to clarify the difference!