I have read some accounts of comfrey being so good at knitting tissue together that it caused parts that shouldn't be together to grow together. For example, people using it as a diaper rash cream and having tissue down there fuse together, requiring surgical intervention. I don't know if this is overblown. I do know comfrey is very powerful at promoting quick tissue growth. I probably wouldn't put it in my eye or in contact with my eye lids personally. Those little bristly hairs seem like they could irritate too.
I like to always use the gentlest plant first, then if that doesn't work, move onto "stronger" plants. If it were me, I would try plantain you mentioned first, since it is so gentle, but still quite powerful in its way. I once had a nasty stye, my eye was swollen almost completely closed. I put a plantain spit poultice on it. Later that day, my eye was completely normal again. So I can certainly attest to its ability to help soothe eye conditions. Violet might also be a good option for an eye wash.
You might find this video about herbal eye washes and eye cups useful too. I believe he gives suggestions for different herbs once could use as well as measures to ensure everything is clean and safe for eyes.