I’ve just found this site that my local library subscribes to (so is free to use with my library card number), for some reason Welsh is not an option on the subscription site but is on the library version (not sure why that would be!) I’m not sure how widely this is available, the link was library specific so I can’t link to it so to find out if a library you’re a member of has access you would have to go to your library website to see if it is listed, and follow their link.
It is mainly vocab/phrases, but looks quite good for hearing the pronunciation as the phrases are spoken by a native speaker (and you have to guess/say what you think it is in English) there is also an option to slow down the speech.
I asked Transparent Language about the lack of a Welsh option, and here is their response:
We only offer one product for learning Welsh called 101 Languages of the World. Languages of the World is designed to help you learn a foreign language for travel, school, business or for your own personal enjoyment. It teaches language Survival Phrases which introduce you to concepts of meeting and greeting, exchanging money, navigating travel situations and much more. Each individual language offers between 1200 and 5,000 words and a variety of phrases perfect for learners who want to brush up or acquaint themselves with another language. If you love all kinds of language or want to experiment with a less commonly taught language, this is the product for you. This software provides speech analysis, interactive conversations, and native speaker pronunciation, all in 101 different languages. Anyone–even complete beginners–can start speaking right away.