That is the currant aphid (Cryptomyzus ribis). The aphids feed on the leaves causes the puckering and distortion you see. You can try washing the aphids from the plant with a strong stream of water from a garden hose. There are a number of natural enemies that feed on the aphids, such as ladybugs, hover fly, lacewings and parasitic wasps. If you use a pesticide, avoid using a broad-spectrum pesticide that will also kill the natural enemies. The mint oil-soap spray you used on the plum aphids should also work here. It looks like a large outbreak, so it may require several sprays. Other options include azadirachtin, which is a narrow range pesticide that will target aphids, and only affects a few natural enemies. During the dormant season you can use a dormant oil spray. For more on this pest, including lifecycle and management options, refer to https://pnwhandbooks.org/insect/small-fruit/currant-gooseberry/currant-gooseberry-currant-aphid