What's the suitable translation of "you guys" or "you lot"? For example,
"Are you lot coming over on Friday?" e.g. informal, you and your friends/family
When referring to "you and your friends/family" exclusively (e.g. you ask one person if they and their friends family are coming over tonight), you'll often just use "ihr" if everybody knows who is addressed.
For example, when I ask my sister:
Kommt ihr Sonntag auch?
Then it is implicitly clear that she, her husband and her children are addressed. This may actually be easier in German than in English, since du and ihr are not the same (as you/you). dict.cc, by the way, lists "ihr" as the single translation for "you lot", indicating that the expression is especially used to differentiate from "just you", i.e. a single person.
This can always be used when it is clear who is addressed. When you're referring to a certain group of friends and talking to one of them, "ihr" may be just right.
If it's only for the informal expression "you lot" then a widely used translation would be almost literal:
"Schaut ihr alle am Freitag vorbei?"
What you'd usually say is
Kommt ihr am Freitag rüber?
IMO, English only uses phrases like "you guys" or "you lot" because there's no other way to distinguish singular and plural in the second person; both forms are identical ("you").
German doesn't need the extension "guys" or "lot" to achieve the same effect: make clear you are talking to and about a group of people rather than a single person.
"Jungs", "Mädels", "Leute", depending on the context and gender.
EDIT: Need to point out, I'm talking about non-formal, but generally polite language. Other forms are certainly possible, again depending on the context and in most cases the general language level people are speaking: "Kommt Ihr heut' rüber, Ihr Schweine?" is somewhat rude, but might be acceptable in some groups.
You lot, you guys and you all/y'all are all primarily workarounds that English speakers employ because sometimes they want to make it clear they are addressing several people. This workaround was not necessary and therefore not used when English still distinguished between second person singular (thou) and plural (ye/you). But then people started to address single people in the plural as a sign of politeness, and through excessive politeness, thou died out completely and left you as the only second person pronoun, regardless of number.
Something very similar happened in Dutch, only faster. Dutch once used a cognate of thou for the singular and a cognate of ye/you for the plural. Once jij/gij, the cognate of you had become the standard even for the singular (by the same mechanism as in English), people felt the need to say things such as gij allen (you all) or gij lieden (you people). As a result, Dutch developed its modern second person plural pronoun, which is an abbreviated form of jij lieden (you people): jullie.
In increasingly large parts of the US we can currently observe the same thing happening with you all and its abbreviation y'all. When I first started taking a Spanish course on Duolingo, for example, it kept marking my English translations wrong if I used plain you as a plural pronoun - it insisted on you all! (I think this has been fixed now.)
I think before this background it's clear what the answer to your question will be: The best German translation for you people / you guys / you all / y'all is almost always a plain and simple ihr. This is because German has not gone through the same process as English and Dutch. (I think this is because third-person forms of address similar to your honour or your grace, but using the plural, became the standard polite form of address before this could happen, resulting in today's polite Sie for singular and plural. It doesn't feel natural to extend this to children or best friends, and in fact the use of Sie is currently declining.)
It is of course possible to say things such as ihr Leute or ihr Typen. But because it is never used as a workaround (since none is needed), it's only ever used for metric reasons or to express a special meaning. (Unless it's a poor translation from English, of course.) The choice of noun is crucial. For instance, ihr Typen would normally only be said by a woman to a number of men with whom she is on very informal terms, in part to stress that there is no woman among them. A generalisation as in American English is out of the question.
FYI "you lot" is British English and "you guys" is American English. "You lot" is less respectful than "you guys" since by being singular it deprives those addressed of their individuality, so a single perfect translation of both will not be possible in my opinion.
Not a literal translation, but I would use something like "ihr alle". The way I understand "you guys" means that "guys" is used to address all members of the group, so I chose "alle" in German.