Differences between charge quantity and electric charge

Charge is a fundamental and inherent physical property of matter and we know that for sure because we can measure it. It is defined:

• by a magnitude, which helps us understand how strongly matter experiences or produces electric, magnetic or electromagnetic fields
• by a unit of measurement, which is a definite magnitude decided by a convention ($C$, $e$, $frac{[Current Intensity]}{[Time]}$, ...)

I'm not exactly sure what you mean by physical attribute or physical quantity but in that case, I believe charge by definition is closer to your third viewpoint

I am not entirely sure of the nuances of meaning, but I hope this helps.

In English we can say "the object is charged", and we can say "the charge on an object is positive" and we can also say "the charge on the object is 3 Coulomb. I think the first and possibly the second treat charge as an attribute, and the third treats charge as a quantity, though I am not sure.

In many situations we need to specify magnitude and sign, so we say "the charge on the object is +3 Coulomb" or "the object has a positive charge of 3 Coulomb.

In Physics we rarely distinguish between an attribute and a quantity. Even when somebody says "water is wet" (an attribute) somebody else will try to find a way to measure it so wetness is not only an attribute but also a quantity.

Electric charge is quantized. For most purposes, the minimum charge is the charge on one electron or positron. Theoretically quarks have charges in 1/3 fractions but they are never observed independently and the amount of charge we observe is never less than the charge on an electron or positron.

A coulomb is a reasonably-convenient unit of measurement for electric charge, created before the quantity of charge per electron was known. It is equal to the charge of approximately 6.2415090744×10^18 positrons.

Electric charge is a physical something-or-other. Nobody knows what it is or why it exists, but like charges repel and opposite charges attract. The force can be measured. Some tiny particles that have no charge turn out to be composite particles made of charged particles. That might be true of all charged particles but there are some like neutrinos for which there is no evidence yet that they are composites of charged particles. Maybe there are fundamental particles which are all charged. Maybe there are fundamental particles and some of them are not charged. I think the latter is more plausible from today's knowledge, but we don't know enough to rule out either choice for sure.

It makes sense to call charge a physical attribute. It is always present in some fixed-point quantity, the quantity is not a continuous number. But for many purposes it might as well be continuous. I don't know whether it makes more sense to say it IS a quantity, or it HAS a quantity. The question may make more sense in Chinese language.

If you look up the NIST website for the SI units https://physics.nist.gov/cuu/Units/units.html you will see that they use both expressions when it comes to charge:"electric charge, quantity of electricity". They are both measured in coulombs so both can be used to designate a physical quantity. At least in the US. Of course, "electric charge" is also a property, an attribute. This is quite common in the common language, not just in physics jargon. Just another example from Physics, "Current" is both the phenomenon and the physical quantity, even though the quantity in some languages is more precisely defined by the equialent of "intensity of the current". So waht will be the point to argue about it? An expression means whatewer people using it want it to mean. As long as you explain what you mean by the expression, the communication is clear and this is the purpose of language.

In the end, I think it does not matter much from the point of view of undertsanding physics even though is interesting from the point of view of language. And it's no point to argue about language; there is no way to settle such arguments by doing an experiment, as we would do to settle arguments about physics.