There is already a pretty good thread on that here:
From what I’ve read and a bit from experience - from training / recovery perspective it’s much better to donate plasma / platelets as it’s actually more usefull (less people donating it - it’s also significantly much longer as compared to blood donation) and there is no downside from training perspective.
That’s what I’m doing on reguler basis and I didn’t notice any impact on my training (except being a bit weaker the day when I give it of course).