erellsworth

Just use Contact Form 7’s normal shortcodes like so:
‘[email* your-email]’ 
‘[checkbox sendinblue-opt-in default:1 “Subscribe” ]’ 
‘[hidden sendinblue-list-id “13”]’
That’s all there is to it.

Contact Form 7 SendInBlue Opt-in Checkbox

Not working

It integrates the form with Send In Blue very well. =)

but if we are using the official SendinBlue plugin, they seem to conflict and the officil plugin stops working.

It is a very useful plugin.

WordPress plugin to add a SendinBlue Opt-in checkbox for Contact Form 7

Muzammil

Gravity Form Sendinblue(brevo) Add On developed for integrate SendinBlue API. 
Using API send data from website to SendinBlue API. 
Used Sendinblue(brevo) API Version 3(V3)
Pro Version: <a href="https://zypacinfotech.com/app/product/gf-sendinblue-pro/" rel="nofollow ugc">Add on for Sendinblue(brevo) on Gravity Forms (Pro)</a>
Key features of the Pro version include:
1 Support for Multiple Contact Lists: With the Pro version, you can easily manage and sync multiple contact lists simultaneously. This allows you to segment your subscribers based on their interests or other criteria, enabling more targeted and personalized email campaigns.
2 Send Phone Number: Expand your reach and engagement by including phone numbers in your contact synchronization. The Pro version enables you to capture and transfer phone numbers along with other contact details, enabling you to leverage SMS marketing and other mobile communication channels.
3 Send Custom Data: Customize your data transfer by including additional custom fields from your Gravity Forms submissions. This feature allows you to collect specific information from your users and seamlessly send it to Sendinblue(brevo), ensuring that you have all the necessary data for effective marketing campaigns.
4 Send Entry Manually: The Pro version grants you the flexibility to manually send Gravity Forms entries to Sendinblue(brevo). This feature is particularly useful when you need to selectively choose which entries to send or if you want to trigger specific actions or automations within Sendinblue(brevo) based on individual form submissions.
<h3>Requirements</h3>
General Features Your Installed WordPress Version Must be a Current Verion 6.0 or More.
Required to Activate Gravity Form before Install this Plugin..
Require an Authentication Key from Your Sendinblue Account…
<h3>Third Party Compatibility</h3>
The vast majority of plugins and themes are compatible with Add on for Sendinblue on Gravity Forms. <a href="https://account.sendinblue.com/advanced/api" rel="nofollow ugc">Our API</a> is available for those that are not. Use the API to customize smart purging, customize cache rules, create cache varies, and make WP nonce cacheable, among other things.
<h3>Privacy</h3>
This plugin includes some suggested text that you can add to your site’s Privacy Policy via the Guide in the WordPress Privacy settings.

Add on for Sendinblue(brevo) on Gravity Forms

Gravity Form Sendinblue(brevo) Add On for Integrate Brevo API to Gravity Form

Contact Form 7 SendInBlue Opt-in Checkbox vs Add on for Sendinblue(brevo) on Gravity Forms