Problem:
The user would like to remove some specific styles in the Toolset common CSS file.
Solution:
Toolset does not have a filter to customize what styles will be added or not. In the upcoming release, we'll introduce a new ID attribute on the body tag to ensure that the user-defined styles in blocks do not get overwritten by themes or plugins. It would be an option in Toolset Settings to enable/disable the body#id tag.
Regarding the rule ".tb-container p:first-child { margin-top: 0 !important }" there is no way to exclude it from the file "toolset-common-es.css". Either include the whole file or exclude it using custom code using wp_dequeue_style
https://developer.wordpress.org/reference/functions/wp_dequeue_style/
You may override it with your custom CSS with a more specific selector, by adding another class to the container:
.tb-container.my-class p:first-child { margin-top: 20px !important }
If you are more comfortable with HTML/CSS/JS, you may want to build using the legacy editor, and the Toolset shortcodes. You can activate the legacy editor in Toolset->Settings->General(tab)->Editing Experience.
Relevant Documentation:
https://toolset.com/documentation/programmer-reference/views/views-shortcodes/