If you have a busy slide and don’t have time to add elaborate animation, consider adding boxes that disappear on a click to reveal information in segments. This will help your attendees focus on one section at a time and stay with you during your presentation: https://youtu.be/5MnAyROoSUQ
If you want to repurpose an existing slide but changing the images will interfere with your animation, use this trick to quickly swap photos and leave your animation in tact: https://youtu.be/Nr7_m7x7ovI