If your existing site uses Video Embedder (opens new window), you can use Video Picker as a replacement.
While Video Embedder doesn't have a field for picking videos, it does use Twig tags to embed videos. Fortunately, these are widely compatible with Video Picker. Take a look at our Embedding Videos page.
{% set embed = craft.videoEmbedder.getEmbedUrl('https://www.youtube.com/watch?v=jfKfPfyJRdk') %}
{% set embed = craft.videoPicker.getEmbedUrl('https://www.youtube.com/watch?v=jfKfPfyJRdk') %}
We're happy to gift anyone a free license for any site they have with Video Embedder installed, to ease the migration to Craft 4 or 5 with Video Picker. Just get in touch with a screenshot of your current site with Video Embedder installed as proof of upgrade.