The ‘transparent’ areas and missing leaf parts can be from barberry looper, a black caterpillar with light dots. Other insects can feed on the leaves such as Japanese beetles.
The overall yellowing could be many things. The soil may be lacking a nutrient, too dry, too wet, or spider mite or aphid damage.
Keep the soil around shrubs moist but not soggy, and treat shrubs for cabbage loopers as outlined in the link, above. Mulch around the shrubs 2-3 inches deep, keeping mulch clear of the stems- do not pile mulch against the base of the plants. Have a soil test done to determine if any nutrients are low, and fertilize according to the results.
Here is a general fertilization guide- https://extension.unh.edu/resources/files/resource000590_rep612.pdf
Use the ‘paper test’ to check for spider mites: tap branches over white paper and look for tiny slow moving mites. Also look for predator mites, which are fast moving, and tiny round, black ladybeetles that feed on the mites. If predator mites are found, spraying may not be necessary.
Look at backs of leaves for aphids: https://extension.colostate.edu/topic-areas/insects/aphids-on-shade-trees-and-ornamentals-5-511/
I hope this helps your shrubs. Thanks for using our service.