Swedish Skitstövel - shit boot, basically means asshole

Hebrew has a non-insult that sounds like an insult - "In your mother". It's not a polite phrase, mind you, but it's not usually used directly as an insult. It has many varied uses. it can be a shorthand for "Swear on your mother's life", mainly to express doubt (ex. "Dude, I won first prize in the lottery!" "really? In you mother!?") or a plea ("I really need a ride right now. In you mother, could you come pick me up?"). It can also be a modifier to "leave me alone", where "leave me in your mother" has about the same meaning as "leave me the fuck alone"/"fuck off".

"live fast and get fucked or whatever"

Not really an insult but it kinda sounds like one.

Li mortacci tua!

Not in my language but it my local dialect "va' in mona" or "va' in figa" both translate to "go to (fuck a) p***y" and are short forms of

Va' in figa to' mare

which suggests the listener should go fuck his own mother's p***y. Very common insult in north-eastern Italy with no equivalent even in standard Italian.