We have finally a Google Sheet Add on:
https://workspace.google.com/marketplace/app/financial_modeling_prep/262992176931
You can see the tutorial here:
https://financialmodelingprep.com/developer/docs/google-sheet-add-on



1. Create a new Google Sheet
2. Select Tools > Script Editor
3. Clik on + beside Files
4. Inside the panel click on Script
5. Name it DelayedImportJSON
6. Copy paste on the right panel the code below:

function DelayedImportJSON(url, query, parseOptions, delay, random) { Utilities.sleep((random ? delay * Math.random() : delay) * 1000); return ImportJSON(url, query, parseOptions); }

7. Click Save Icon
8. Clik on + beside Files
9. Inside the panel click on Script
10. Name it ImportJSON
11. Copy Past on the right panel the code from URL: https://raw.githubusercontent.com/bradjasper/ImportJSON/master/ImportJSON.gs
12. Modify the code by changing this part:

if (!data[row][column]) {
if (row < 2 || hasOption_(options, "noInherit")) {
data[row][column] = "";
} else {
data[row][column] = data[row-1][column];
}
}


into this:

if (data[row][column] == null) {
if (row < 2 || hasOption_(options, "noInherit")) {
data[row][column] = "";
} else {
data[row][column] = data[row-1][column];
}
}


13. Click Save Icon
14. Reload the page
15. Now to get last 3 Apple income statements you need to type =DelayedImportJSON("https://financialmodelingprep.com/api/v3/income-statement/AAPL?limit=3&apikey=YOUR_API_KEY") in a cell you want data to be.

The link to full template is here.