These are some of the free, freemium and premium tools that I have come across in my travels and would recommend you take a look at.
Page speed & performance tools
- waterfaller.dev – feedback on CWV scores for any URL, with handy Jira user stories on each issue to copy and paste
SERP analysis tools
Technical SEO tools
Link building and domain auditing tools
- Marketing Signals Tools – a selection of free tools to audit links and domains