I have created a script, which automatically checks and update if necessary, the Let's encrypt Wildcard SSL certificate on Mikrotik devices.
http://me.sdnix.com/mikrotik-lets-encry ... rtificate/
In few words, it checks if there is a certificate and if the cert.pem and privkey.pem are up to date (certbot is changing them if there are less than 30 days from expiry of domain). If there is no certificate on the Mikrotik device, script automatically upload and configure it. If the cert.pem and privkey.pem are not up to date, it takes the new files, upload it to all the Mikrotik devices and configures new certificates on the devices.
Take a look and if someone has any questions/recommendations/comments - here to answer