Ubi launcher used to have (or still does?) a high cpu use with overlay enabled, don't know if Epic launcher has same.
Try turning off different settings/notifications in them, see if that helps.
My PC- Ryzen 5 5600x, B550 aorus pro ac, Hyper 212 black, 2 x 16gb F4-3600c16dgtzn kit, NM790 2TB, Nitro+RX6900XT, RM850, Win.10 Pro., LC27G55T.