The full question

What is the best way to personalise a portfolio for multiple companies without putting in too much effort?

My two cents

Typically, when you create a portfolio, it is common practice to create one and send it to multiple companies.

But, it's important for companies to see that your application material is tailored specifically for them. This shows that you are not just interested in any job, but the job at their company.

To show your respect for the job position and willingness to work for a particular company, a simple way is to adjust your portfolio based on the job post.

For example, you can order your projects based on the list of requirements. Or you can change the titles of your projects to highlight the specific skills that they want to see in a candidate.

The content of your portfolio doesn't really change, it's what you highlight that changes.