"The German comes from Germany."
Translation:La germano venas el Germanio.
Yes to both.
In modern usage, germano refers to a person from Germany, male or female. Since most of the time, the sex of the person is irrelevant to their being from Germany, I would say that this is the preferred form.
If, on the other hand, you feel the need to explicitly refer to the sex of this German person, you can use germanino for the ladies.
For the gents, you have three choices: You can be exceptionally sexist and declare that germano is male because that's how Zamenhof wrote the language (and thus can never be wrong). You can use the "official" but perhaps one of the ugliest forms in Esperanto, virgermano. Or you can use the unoffical (Eeeek, heresy! But much more satisfying to my ears) germaniĉo. If you do use germaniĉo, then just beware of angry lynch-mobs of purists running after you screaming at the top of their lungs, because Esperanto can never change (see option 1).
It seems there are no obligatory rules in Esperanto: http://bertilow.com/pmeg/gramatiko/propraj_nomoj/majuskloj.html (in Esperanto)
Is there no word "eliras"?
There is, but it means "to leave [a place]" (as in, go from in that place to outside that place), and not "to come from [a place]". So
"La germano iras ekster Germanion."
"La germano eliras Germanion."
would mean roughly the same. ("The German goes to outside of Germany." or "The German leaves Germany.", respectively. Both are quite different in meaning from "The German comes from Germany.")
Why are words like germano and usonano not capitalized, [...]
Esperanto considers country names proper names. And proper names are capitalized in Esperanto. Names of peoples and demonyms (words for members of those peoples or words for citizens of a country or state) are (for whatever reason) not considered proper names in Esperanto. They may be capitalized (because they're usually related to a country name), but usually aren't. (See chapter 35.5. Majuskloj kaj minuskloj ĉe propraj nomoj, section Landoj, popoloj kaj lingvoj in PMEG.)
[...] but Esperantisto apparently capitalized?
Other than language names derived from peoples' names (la germana, la angla) or country names (la nederlanda), "Esperanto" is a proper name and thus capitalized. This goes also for other such non-derived language names, which are all proper nouns with an -o ending: "Sanskrito", "Volapuko", "Latino".
In the case of "Esperanto", this capitalization is often needed to avoid confusion, because "esperanto" (non-capitalized) is an actual Esperanto compound word with a meaning different and independent of the language name:
- esper·i — to hope
- -ant- — present active participle ("doer" of the "action" in question)
Thus "esper·ant·o" means "hoper" or "someone who hopes".
"Dr. Esperanto" was actually a pseudonym of the founder of Esperanto, Dr. L.L. Zamenhof and the pen name under which he published the first works about that language (which he back then called "la lingva internacia" or "la internacia lingva", i.e. "the international language"). Only later did others use "Esperanto", based on his pseudonym, as the de-facto name of the language and did he reveal his identity (and he did accept "Esperanto" as the name for the language).
Words derived from "Esperant·o" are often (but not always) also capitalized to distinguish them from words derived from "esper·i" + "-ant-". This is more relevant for "Esperant·a" (pertaining to the Esperanto language) vs. "esper·ant·a" ("hoping") than for "Esperant·ist·o" (Esperanto speaker) vs. "esper·ant·ist·o" (what would this even mean? Someone whose job or conviction it is to be hoping? Certainly not something one would commonly use.), but for consistency, many capitalize all words derived from "Esperanto", including "Esperantisto".
Because "la germana" nearly always implies "lingvo" (just for the reason of being so frequently used in this context) and not "homo/vir(in)o/persono". If you want to say "(the) German (language) comes from Germany" then you can say "La germana venas el Germanio". Otherwise you would need specific context, e.g. "la viroj venas el diversaj sxtatoj. La greka (viro) venas el grekio, la franca (viro) venas el francio. La germana (viro) venas el Germanio."
"estas de" is used a lot in Esperanto, to say that someone was born or grew up in a country or at a place or usually lives there (is a resident there).
"comes from" can mean all that, but can also mean that someone only currently travelled from there and now arrives here. "venas el" has the same meaning(s), so it's the correct translation for this sentence.