Maybe think again about the temporary one. I’m not saying definitely don’t do it, but maybe look at it like this.

If one of my daughters did that, I wouldn’t be self-controlled enough to lie and say “I thought I’d never say this, but that doesn’t look half bad,” but many (maybe most) mothers would. And their sons/daughters would never know just how upset they felt inside.

As I can be rather volatile, I’d probably come out with something mean that I’d deeply regret later, about how upset I was, and how selfish to think that I’d appreciate it etc etc which would be impossible to really take back even if the temporary tattoo was washed off. I also hate being misled, so I’d be very upset that I’d been tricked into thinking it was real. Maybe more my problem, but relationship-damaging all the same. (And I’d probably see the gift as trying to buy my approval, which is what it’s for really, isn’t it?) Yes, I need to chill a bit more.

As you said, it’s the thought that counts. Is the thought about how much you love tattoos, or how much you love your mum? Talking to her about why she feels upset by them, and maybe giving her time to reconsider and see why they mean so much to you and that you would like to dedicate one to her, might be a much gentler way to show her what she means to you, and she might well change her mind given time. (I’m not keen on tattoos and luckily neither of my daughters are either, but if they changed their minds, and I knew it meant a lot to them, I’m sure I’d come round eventually.)

Hope things work out happily for you and your mum.