Words with no direct English equivalent
A few words with their closest definitions/meanings included:
"Hiraeth (Welsh)": A homesickness for a home to which you cannot return, which maybe never was; the nostalgia of the lost places of your past
"Lagom (Swedish)": Not too much, not too little, but just right
"Tartle (Scottish)": The panicky hesitation just before you have to introduce someone whose name you can't quite remember
"Hygge (Danish)": the pleasant, genial, and intimate feeling associated with sitting around a fire in the winter with close friends.
"Litost (Czech)": a state of torment created by the sudden sight of one’s own misery.
Another word with no direct English definition is "Packesel" (which is German), which goes something along the lines of: "the person who’s stuck carrying everyone else’s bags on a trip."
What other words have no straightforward English equivalent?
Saudade is a popular one in Brazilian Portuguese (perhaps EU Portuguese, Idk tbh haha). Basically it means nostalgia or an extreme longing for something or someone that's perhaps unattainable. For example, if I was in a relationship and it ended and I was having a Drake, Adele, Lana Del Rey, and entire tub of ice cream moment, it'd probably be because of "saudade" for that person/relationship.
Here are other Tagalog words I know
Tampo - when you're showing someone that you're mad at them, although you're not really that mad. Usually, the person doing this wants the other person to make it up to them.
Gigil - the urge of pinching someone out of cuteness. It may also be a word for suppressed anger that you can't let out.
Torpe - someone who feels shy about expressing their attraction to a person they like.
Gezellig - (Dutch) Kinda like a warm and cozy feeling, intimate, sociable
"Op Kerstavond zaten wij allemaal bij de haard terwijl het buiten sneeuwde. Het was zeer gezellig"
"On Christmas Eve we all sat by the warm fireplace as it snowed outside. It was very cozy"
Imperium - (Latin) kinda like "power to command" and one who has it is an imperator. Imperium is usually translated as 'empire' such as "Imperium Romanum"
"Imperator Romanus imperio multo usus erat dum patriam eius regebat"
"The Roman Emperor used much imperium while he ruled the country"
やっぱり (yappari), or やはり（yahari) in Japanese, used to convey diverse versions of "confirming a presumption", and may have a range of English translations, like (After all), (I knew it), (It is, isn't it!), and others, non of which being a mirror-image equivalent of what the word conveys in Japanese.
German: Ohrwurm - A melody that got stuck in your head and you keep singing it
Czech: Bufetit (verb), bufeťák (a person) - To eat thrown away food (like from a dustbin) or to dig through trash. "Bufeťák" can be a homeless person or you can tell it about a dog that loves eating anything at least resembling food.
Akorát - Just the right amount.
And I disagree with your word "lítost". Lítost can be translated as "sorrow, grief, regret, remorse". Maybe you meant "sebelítost" byt my dictionary shows the English translation "self-pity".