"q" is common in Latin scripts from early in their history. The lower-case "q" is common since Caroline-script times.
"4" exists in Latin scripts (in its modern form) from the 14th century onward and is common from the mid-15th century onward.
"4o" is common Latin scripts from about the 14th century onward, depending on the language (especially in Romance languages for writing ordinal numbers).
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Having said that, I'm not sure EVA-q is a 4 or a q shape. It might be a sword-shape written with a swoosh to obscure it or to make it easier/faster to write. It might be a staff shape or a cross shape. The stem is quite long, so it's not necessarily the numeral-4 shape. It might be a vertical bar with a ligatured "c" character or a vertical bar with an obscuring triangular shape.
"4" exists in Latin scripts (in its modern form) from the 14th century onward and is common from the mid-15th century onward.
"4o" is common Latin scripts from about the 14th century onward, depending on the language (especially in Romance languages for writing ordinal numbers).
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Having said that, I'm not sure EVA-q is a 4 or a q shape. It might be a sword-shape written with a swoosh to obscure it or to make it easier/faster to write. It might be a staff shape or a cross shape. The stem is quite long, so it's not necessarily the numeral-4 shape. It might be a vertical bar with a ligatured "c" character or a vertical bar with an obscuring triangular shape.

