Is it okay to make a plugin to the WordPress repo, but limit it’s actions to maximum N events?

Trialware is not permitted (props @jacob):
https://developer.wordpress.org/plugins/wordpress-org/detailed-plugin-guidelines/#5-trialware-is-not-permitted

With the only exception being

Attempting to upsell the user on ad-hoc products and features is acceptable, provided it falls within bounds of guideline 11 (hijacking the admin experience).

https://developer.wordpress.org/plugins/wordpress-org/detailed-plugin-guidelines/#11-plugins-should-not-hijack-the-admin-dashboard

Sounds like the feature must be in a separate plugin itself to be within the guidelines for submitting a plugin to WordPress.org

Just make sure you’re not that guy that has a plugin that’s super annoying trying to upsell 🙂

Hata!: SQLSTATE[HY000] [1045] Access denied for user 'divattrend_liink'@'localhost' (using password: YES)