Unfortunately it is impossible to clear all passwords at one in Chrome. But since it is written with web technologies, you can navigate through DOM and ShadowDOM. It works with Chrome v84.

clearChromePasswords.js

// Unfortunately it is impossible to clear all passwords at one in Chrome.
// But since it is written with web technologies, you can navigate through DOM and ShadowDOM.
// It works with Chrome v84.
// 1. Go to chrome://settings/passwords
// 2. Open console, paste code below or run it as a snippet in devtools

(() => {
    const interval = setInterval(() => {
        const kebabMenu = document.querySelector('settings-ui').shadowRoot.children.container.querySelector('settings-main').shadowRoot.querySelector('settings-basic-page').shadowRoot.querySelector('#basicPage settings-autofill-page').shadowRoot.querySelector('#pages settings-subpage #passwordSection').shadowRoot.querySelector('#passwordList').querySelector('password-list-item').shadowRoot.querySelector('cr-icon-button#passwordMenu');
        const removePasswordButton = document.querySelector('settings-ui').shadowRoot.children.container.querySelector('settings-main').shadowRoot.querySelector('settings-basic-page').shadowRoot.querySelector('#basicPage settings-autofill-page').shadowRoot.querySelector('#pages settings-subpage #passwordSection').shadowRoot.querySelector('#menu #menuRemovePassword');
        kebabMenu.click();
        removePasswordButton.click();
    }, 200);
    const whenShouldStopInterval = 60 * 1000;
    setTimeout(() => clearInterval(interval), whenShouldStopInterval);
})();