Coin 1: Aidan, can you verify it's a match for Spanish Netherlands? I'm not so sure; I can't find anything anywhere that matches the reverse legend: GECT Z POVR LE BVREAV DES FINA. It's either from some small Burgundian territory somewhere or it's an "evasion", a counterfeit with a deliberately bogus legend.
Coin 2 is I assume the same one discussed in your
earlier thread but you've now got both sides of the coin, which helps in narrowing down the ID of the ruler and state of issue.
The name of the ruler given on the obverse is IOAN FRID SECVNDI, also known as Johann Friedrich II (or John Frederick II, if you wish to "de-germanise" it).
I have found a Johann Friedrich II as Duke of Ernestine Saxony (also known as Saxe-Coburg-Eisenach), 1554-1595. The coin is undated, and most German states were dating their coins by the 1600's so it fits the timescale reasonably well. Unfortunately, Krause doesn't go back to the 1500's yet. Anybody got the German States book?

Coin 3 is in the 1600's Krause: it's a 15 krajczar, KB mintmark (Kremnitz mint). The "XV" in the oval below the portrait is the deniomination, and if you're wondering how to pronounce "krajczar", it's presumably the Hungarian spelling of the German word "kreutzer".
KM#208, CV is $40 in VF.
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