The habit of forgetfulness is considered as a bad habit, especially if it is exhibited in dharmic activities. That is, if a person is bounded to perform a duty and exhibits incautiousness towards such activities, then it maybe considered as a sin.
While enumerating that qualities that a king should not possess, Narada mentions incautiousness also
Dost thou ...
Not all sinners will get moksha directly although they die in Varanasi. Some has to become Pisacha and they will get liberated afterwards.
But it should be noted that no one who dies in Varanasi will born again including living animals.
Sinners, in this context, can be divided into two kinds: Sinners who committed their sins at Varanasi and sinners who ...
There is no mention of any process or technique by which anything is transferable from one person to another.
In fact, to the contrary, everything about a person completely sticks to that individual alone.
For example, Brhadaranyaka Upanishad 4.4.2:
तं विद्याकर्मणी समन्वारभेते पूर्वप्रज्ञा च
His deeds, his knowledge and his past impressions follow him.
Papa and Punya is not defined in absolute term. Gita in Ch.4 solka 17 says गहना कर्मणोगति (The intricacies of action are very hard to understand.).
As an example read the story of Mandavya in Mahabharat (here). Even the great Rishi is punished for a small trivial action.
Vyasa knows the best. He says:
"Ashtadasa Puraneshu Vyasena Vachanam Dwayam, ...