You can combine the two functions into one by checking e.target.id inside, and select both input values at once to loop through and add the event listener:

const suprqMean = 3.93;
const usabilityMean = 4.06;
const suprqSD = 0.29;
const usabilitySD = 0.29;

document.querySelectorAll("[id^=formGroupExampleInput").forEach(el => {
  el.addEventListener("change", updateValue);
});

function updateValue(e) {
  inpVer = e.target.id === "formGroupExampleInput" ? true : false;
  outEl = inpVer ? suprq : usability;
  outVal = inpVer ? (e.target.value - suprqMean) / suprqSD : (e.target.value - usabilityMean) / usabilitySD;
  outEl.textContent = outVal;
}

<form class="leftForm container">
  <div class="form-group">
    <label for="formGroupExampleInput">SUPR-Q raw</label>
    <input type="number" class="form-control" id="formGroupExampleInput" placeholder="SUPR-Q raw">
  </div>
  <div class="form-group">
    <label for="formGroupExampleInput2">Usability raw</label>
    <input type="number" class="form-control" id="formGroupExampleInput1" placeholder="Usability raw">
  </div>
</form>

<table class="table table-striped table-dark">
  <thead>
    <tr>

      <th scope="col">Z-Score</th>
      <th scope="col">Result</th>

    </tr>
  </thead>
  <tbody>
    <tr>

      <td>SUPR-Q:</td>
      <td id="suprq"></td>

    </tr>
    <tr>

      <td>Usability:</td>
      <td id="usability"></td>

    </tr>
  </tbody>
</table>

Looks like you are somewhat repeating yourself in that JS code.

The usual remedy for this would be to refactor the repeated code into a reusable function:

const suprqMean = 3.93;
const usabilityMean = 4.06;

const suprqSD = 0.29;
const usabilitySD = 0.29;


function listenForChanges (inputId, logId, output, mean, SD) {
  const input = document.querySelector(inputId);
  const log = document.querySelector(logId);

  input.addEventListener("change", updateValue);

  function updateValue(e) {
    output.textContent = (e.target.value - mean) / SD;
  }
}

listenForChanges("#formGroupExampleInput", "#suprq", suprq, suprqMean, suprqSD)
listenForChanges("#formGroupExampleInput1", "#usability", usability, usabilityMean, usabilitySD)

Something else feels weird though. In your original snippet (and in mine too) there are references to two variables that are never declared: suprq and usability.

But apart from that, do you like this use of a function as a first step to make the code a little bit less "awful"?

If you have many of these, the next step could be to make a data structure for all the input pairs and call this function on each pair with a loop:

const all = [{
  inputId: "#formGroupExampleInput",
  logId: "#suprq",
  output: suprq,
  mean: 3.93,
  SD: 0.29
}, {
  inputId: "#formGroupExampleInput1",
  logId: "#usability",
  output: usability,
  mean: 4.06,
  SD: 0.29
}]

all.forEach(listenForChanges)

function listenForChanges ({inputId, logId, output, mean, SD}) {
  const input = document.querySelector(inputId);
  const log = document.querySelector(logId);

  input.addEventListener("change", updateValue);

  function updateValue(e) {
    output.textContent = (e.target.value - mean) / SD;
  }
}

Notice that I changed the function a bit here, having it accept a single object parameter instead of a series of parameters. This is just to make it easier to glue everything together with forEach.

Here's is a 'condensed' version

const values = {
  suprqMean: 3.93,
  usabilityMean: 4.06,
  suprqSD: .29,
  usabilitySD: .29
};
["suprq", "usability"].map((slug => {
  document.querySelector(`#${slug}Input`).addEventListener("change", (clicked => {
    document.getElementById(`${slug}`).textContent = (clicked.target.value - values[`${slug}Mean`]) / values[`${slug}SD`]
  }))
}));

<form class="leftForm container">
  <div class="form-group">
    <label for="formGroupExampleInput">SUPR-Q raw</label>
    <input type="number" class="form-control" id="suprqInput" placeholder="SUPR-Q raw">
  </div>
  <div class="form-group">
    <label for="formGroupExampleInput2">Usability raw</label>
    <input type="number" class="form-control" id="usabilityInput" placeholder="Usability raw">
  </div>
</form>

<table class="table table-striped table-dark">
  <thead>
    <tr>

      <th scope="col">Z-Score</th>
      <th scope="col">Result</th>

    </tr>
  </thead>
  <tbody>
    <tr>

      <td>SUPR-Q:</td>
      <td id="suprq"></td>

    </tr>
    <tr>

      <td>Usability:</td>
      <td id="usability"></td>

    </tr>
  </tbody>
</table>