a.おお、そうじゃ、わしが知っておるんじゃ
b.あら、そうよ、わたくしが知っておりますわ。
c.うん、そうだよ、ぼくが知ってるよ
d.んだ、んだ、おら知ってるだ。
e.そやそや、わしが知ってまっせー
f.うむ、さよう、せっしゃが存じておりまする。
a=老人=The elderly
b=お嬢様=In Japanese, it generally refers to the daughter of a wealthy or aristocratic family
c=男の子＝Boy
d=田舎の人=Country people
e=関西人=People in Kansai, Japan
f=武士=warrior/ Samurai
男：おれは、この町が大好きだぜ。
女の子：あたしは、この町が大好きなのよ。
老人：わしは、この町が大好きなんじゃ。
男の子：ぼくは、この町が大好きさ。
お嬢様：わたくしは、この町が大好きですわ[1]。
説明（せつめい）Explanation：
- 男：I personally don't recommend male's "役割語", because the self-proclaimed "おれ" would appear to be very rude and impolite. "だぜ" often appears in the same sentence as "おれ", which generally shows that the person has a very rough personality.
- 女の子："あたし" is only available for women，"よ" In addition to telling others what it means, there is actually a more gentle and lovely tone.
- 老人："わし" must be used by the elderly, "なんじゃ" can be replaced with "なんです" here,“なん”there is an emphatic tone.
- 男の子："ぼく" is generally used by boys or young men, but also by girls or young women. "さ" here only strengthens the tone, and has nothing to do with the objective judgment I mentioned earlier.
- お嬢様："わたくし" is a very solemn expression, but also self-effacing, "ですわ" is to show a sense of elegance and nobility.
- 関西人：This is just a dialect, and it will be very difficult, so I won't expand it in detail.
Finally, let's take a look at this "Samurai". In fact, it's not just the "Samurai" class who said that, but the "Emperor" basically said that. For example, I used to watch FGO's Anime, the tone of the Roman Emperor Nero was like this. うむ is what she says most often.
- うむ、さよう、せっしゃが存じておりまする。=はい、そっか、わかった=Well, that's it, I understand.
In fact, the words うむ, さよう, and せっしゃ are hardly used by modern Japanese. 存じております will be used because it is honorific.
うむ is a term that reflects the identity. (Modern Japanese rarely use うむ, and basically use はい to express affirmation.)
The Emperor generally uses "余（yo）" to call himself.
The Samurai normally calls himself "せっしゃ".
About 役割語（all？）：
Sorry, I can't list them all, because they are too many. If you are interested, just leave a comment to tell me, I will write more.
If you can ask specific questions, I can give specific answers.
References:
[1] https://www.jpf.go.jp/j/project/japanese/teach/tsushin/reserch/201302.html