The British Lymphology Society (BLS) issued this advice on 10/02/2021:

Coronavirus Vaccine Advice

Please advise anyone who has lymphoedema that lymph node swelling can be a side effect of any vaccine but is a known side effect of both the Moderna and Pfizer COVID-19 vaccines. However, we strongly urge that they accept whichever vaccine is offered, providing they have no contraindications.

As per previous advice from Prof. Peter Mortimer, anyone with lymphoedema of the arm is advised to get the vaccine in the opposite arm or thigh.

This advice also applies to those who do not have lymphoedema but who have been treated for breast cancer. They should request the vaccine in the opposite arm from their breast cancer treatment. If they have had lymph nodes removed or treated on both sides, the injection should be in the thigh or buttocks.

The Pfizer and Moderna COVID-19 vaccines documents confirm it may be given in the thigh. This is stated on the vaccine documents in a footnote.