Below is a list of my favourite free WordPress plugins.

All-in-One WP Migration

Asset CleanUp: Page Speed Booster

AutoOptimize

Black Studio TinyMCE Widget

Coming Soon Page & Maintenance Mode by SeedProd

Contact Form 7

Disable Comments

Duplicate Page

Feature A Page Widget

File Manager

GDPR Cookie Consent Banner

Google Analytics Dashboard Plugin for WordPress by MonsterInsights

iThemes Security (formerly Better WP Security)

Jetpack by WordPress.com

MailPoet – emails and newsletters in WordPress

ManageWP Worker

Media Cleaner

Media Library Assistant

Page Builder by SiteOrigin

PB SEO Friendly Images

Really Simple SSL

Redirection

Regenerate Thumbnails

SiteOrigin Widgets Bundle

Smash Balloon Social Photo Feed

Smush Image Optimization, Compression, and Lazy Load

Timeline Express

WooCommerce

Wordfence Security – Firewall & Malware Scan

WP Fastest Cache

WP Mail SMTP by WPForms

WP Simple Adsense Insertion

WP-Optimize – Clean, Compress, Cache.

WP-Spreadplugin

Yoast SEO