Being a B2B company does not automatically mean that EU GDPR does not apply to you. You could be providing services( as a processor) to another company ( as controller) but while doing that you might be processing data of individuals. For example, a marketing company “A” performing an SMS campaign on behalf on company “B”. Company “B” would be processing data of individuals even if the individuals themselves are not customers of company “B”.
So, “directly” processing data as a controller in not the only prerequisite for the EU GDPR to be applicable to you.
Also, if you are established in the EU that would make you a controller in terms of processing data of your employees so the EU GDPR would be again applicable.