.

That isn't how chemistry works.

Isosaccharinic acid has the same chemical formula (C6H12O6) as glucose, which isn't acidic. However, they both have the same net charge.

When something is an acid, it dissociates into both a positive ion H+ and negative ion (rest of the molecule)

HA ⇌ H+ + A-

You're right but a lot of times the positive ion is far less reactive and/or more massive than the negative ion. Not so much for OH-. Charge is not the only thing that matters.

Well, in a similar way to how you can't generate a negative ion without simultaneously generating a positive ion... how do you use the negative ion in a reaction without simultaneously using the associated positive ion in the same reaction?

Here's one way

https://en.wikipedia.org/wiki/Ion-exchange_membrane

Another, that you might be interested in, but it's more confusing

https://en.wikipedia.org/wiki/Proton-exchange_membrane

See the figure

https://www.fuelcellstore.com/introduction-ion-exchange-memb...

Each ion of salt participates in a different reaction