らしい ①Seems like, Apparently, I heard

The main difference between そう and らしい① lies in the source of information. そう implies speculation based on personal observation, e.g. 面白そう ('It looks interesting.'). らしい is based on secondhand information or inference, e.g. 面白いらしい ('I hear it's interesting.' or 'Apparently, it's interesting.').

らしい ① and にみえる both express observations, but differ in nuance and formality. らしい ① suggests hearsay or information from a third-party source, e.g. 知っていたらしい ('Apparently he/she knew.'). In contrast, とみえる is more formal and expresses the speaker's deduction based on evidence, e.g. 知っていたと見える ('It appears he/she knew.', as if drawing a conclusion based on evidence).

ということだ and らしい ① both convey information from another source, but differ in nuance and formality. らしい ① conveys hearsay with a nuance of confidence, e.g. 雨が降るらしい ('Apparently, it's going to rain.'). In contrast, ということだ literally means 'It is said that (A).' or 'The word is that (A).', and sounds more formal and confident than らしい ①.

んだって and らしい ① both convey information from another source, but with different nuances and levels of formality. らしい ① suggests hearsay with a nuance of certainty, indicating the speaker believes it to be true, e.g. 'Apparently it's (A).'. In contrast, んだって is highly casual and includes an explanatory nuance, similar to 'He/she/they said/say (A), you know.'.

みたいに・みたいな and らしい① both convey a sense of 'seems', but differ in nuance and usage. みたい compares something to something else, e.g. 春みたいに暖かい ('It's warm like spring.'). らしい expresses hearsay or inference, e.g. 暖かいらしい ('Apparently it's warm.' or 'It seems warm.' based on what was heard or observed.).

Both forms express observations similar to 'seems' or 'appears,' but differ in nuance. ようだ is based on direct information or experience, e.g. 雨が降るようだ ('It seems it will rain.', based on people carrying umbrellas). らしい① implies indirect or secondhand information, e.g. 雨が降るらしい ('I heard it will rain.' or 'Apparently, it will rain.')

Both らしい① and みたい express similarity, but with different nuances. らしい means something is typical or characteristic of what it represents, e.g. 春らしい天気 which implies 'weather that's just like spring should be'. In contrast, みたい suggests resemblance of one thing to something else that it is not, e.g. 春みたいな天気 'spring-like weather' such as an unseasonably warm day in winter.

っぽい and らしい ① both describe being 'like' something, but with different nuances and formality. っぽい, similar to the English '-ish,' refers to having the characteristics of something without being that thing, and is very casual, e.g. 子どもっぽい態度 'childish behavior', e.g. from an adult. In contrast, らしい ① implies embodying a characteristic in a more fitting or expected way, e.g. 子どもらしい笑顔 'a smile just as you'd expect from a child'.

らしい has two related but distinct functions. らしい ① conveys information heard from a third-party source with a nuance that the speaker believes it to be true, e.g. 雨が降るらしい ('Apparently, it's going to rain.'). らしい ② serves as an adjective, describing a typical characteristic, e.g. 春らしい天気 'spring-like weather'.

どうやら and らしい are often used together to express conjecture based on indirect evidence. どうやら softens the statement and suggests uncertainty, while らしい indicates that the information is based on hearsay or external sources. For example: どうやら雨が降るらしい (Apparently, it’s going to rain).

Both らしい ① and にみえる can convey observations, but with different nuances. らしい ① implies hearsay or information from a third-party source, e.g. 雨が降るらしい ('Apparently it's going to rain.'). In contrast, にみえる expresses a direct visual observation, e.g. 雨が降るようにみえる ('It looks like it's going to rain.', based on visual cues like the sky).

らしい ① and そうだ both convey information heard from another source, but with different nuances. らしい ① suggests hearsay with some degree of certainty, implying the speaker believes it to be true, e.g. 'Apparently it's (A)'. In contrast, そうだ is more neutral, simply meaning 'I heard (A).' or 'They say (A).'. They also connect differently to nouns and な-Adjectives, e.g. 大変らしい vs. 大変だそうだ (both meaning 'It seems difficult.').

らしい ① and ときいた both convey information obtained from another source, but with different nuances. らしい ① expresses hearsay, with the nuance that the speaker is relatively confident about the information, e.g. 雨が降るらしい ('Apparently, it's going to rain.'). In contrast, ときいた literally means 'I heard (A)', with no implication about the speaker's belief, and it cannot be used for information obtained from e.g. written sources.