how to transfer cash to my Monzo card whilst abroad

I am travelling to Spain soon and would like to know if I can deposit cash to my Monzo account whilst in Spain? I know I can do it via a Paypoint in the UK.

No. There is no facility to deposit into your Monzo account when in Spain.

Maybe some money transfer company like Western Union might do it for a fee?

Curious about the use case here. Whilst in Spain you will receive GBP cash and would like to deposit it?

No. I have purchased Euros in cash, but was concerned that restaurants and bars will not accept cash, as is the case here in the UK. If that is the case then I will have to pay by card, hence my question about adding cash Euros to my Monzo card account

Don’t be concerned, 99% of establishments in Spain will accept cash.

A better plan would have been to rely on your card and withdraw cash as and when necessary.