Is it possible to cross-launch from an event in BHOM to the incident in ITSM?

There is nothing currently available out of the box for this. It is easily achievable though by creating an event advanced enrichment policy like the following example:

a) Event selection criteria is of class INCIDENT_INFO and status OPEN.
b) Lookup an old MonitorEvent class event where _identifier slot matches incident_relation_source of INCIDENT_INFO event.
c) Use concat function to concat two strings. The first string is the fixed part of the URL which never changes and the second string is the value of incident_id slot of the INCIDENT_INFO event.
d) Use AddNote function or set a slot value with the string from step c.

Attached is an example event policy in json format which will add a note with the URL. This can be imported with a POST call to API /events-service/api/v1.0/event_policies using jwt token.