Air carrier Captain reported the Right Engine N1 vibration increase during cruise. Flight diverted to a safe landing.

Narrative

IMC; at FL340 (SAT -47C); we encountered moderate turbulence for approximately 1 minute and simultaneously observed a strong ozone odor. Soon afterwards; R Eng N1 vibrations were noted at 2.6 and climbing (amber band). All other R Eng indications and all L Eng indications were normal. We conducted the (757) Engine Vibration Non-Normal procedure which led us to the (757) Ice Crystal Icing procedure. We turned approximately 30 degrees left to expedite exiting IMC conditions. R Eng N1 Vib continued to climb to 5.0; all other engine indications appeared normal; although a noticeable vibration was felt in the airframe. I then initiated a call with dispatch and Maintenance Control. During this call we exited the IMC conditions and R Eng Vib slowly started decreasing. Diversion options were first discussed at this time. I made the decision (with Dispatch and Maintenance Control concurrence) to closely monitor R ENG performance; and if the N1 Vib returned to normal operating range by the point we were abeam ZZZ; we could continue. When we were abeam ZZZ; the R Eng N1 Vib were fluctuating 3.2 to 3.5; still in the amber band. We then diverted to ZZZ1 without incident; conducting the overweight landing Non-Normal checklist enroute. During descent; R Eng N1 Vib returned to normal operating range and normal approach and landing was accomplished. Maintenance was waiting for us at the gate and we conducted a thorough verbal debrief.