I don't think there are such adverbs in English that officially indicate the speaker's emotional/mental state, personality, etc.
"Could you please let me join your group?" doesn't convey the intensity of desperation in writing. We would have to hear people request, beg, etc. to know exactly what they mean by please in such a request. I heard that some foreign languages have adverbs that specifically nitpick a desperately pleading speaker.
(Judgmental warning) With many women, I notice the frequent use of the word completely, especially for adjectives not subject to completion, or for verbs that already denote completion.
- I was completely pissed that he was 2 minutes late.
- That movie was completely stupid.
- I'm avoiding that class because I hear it's completely difficult.
- That pig completely finished all the leftover food.
From experience and as I've been told, this over-usage of "completely" denotes someone who has very high, unrealistic, and unfair expectations. I believe the usage is acceptable, though not the best choice of adverb in many cases; but the choice and frequency just ought to say something about the speaker.
I think English adverbs modify only verbs, adjectives, and other adverbs, but not the speaker. I just have that yearning for adverbs to also be able to depict the speaker's psyche.