At the moment, there are no plugins to integrate the questions and answers in Musing.io with Wordpress blogs. I don't see the need for one, either. At least, not at the moment.
While integration with other sites could be a good way to increase Musing.io's audience and enrich it's user experience, it's important that the platform be selective with who they integrate with and how, especially this early in its development. In this respect, I don't see a plugin or feature that will integrate Musing.io with a Wordpress site like you described to be good for Musing.io right now.
First, using your words above, you want to "build a Wordpress blog based on the questions asked on Musing". What do you mean by this? Do you mean you want to take the questions and answers written by the different users from Musing.io and post them in a feed to your website? If that's the case, then your blog could infringe on the copyright of users like me who didn't give permission to have the content I wrote in the Steem blockchain to be published off-chain. Worse, if someone decides to make a copyright complaint, you could also be endangering the Musing.io platform or whoever made that plugin by making them liable to copyright violation, as well. So, let's not forget that just because we are in a blockchain where decentralization and anonymity are valued, doesn't meant that we can violate copyright and ownership laws, where they apply.
Second, a two-way integration with Wordpress could just take users away from the platform. Again, Musing.io is still new. According to SteemReports.com, for example, only 330 users were active on the platform over the last 7 days. If you start placing Musing.io content elsewhere, then you're just encouraging these 330 users to spend their time somewhere else, further decreasing the activity on the main Musing.io platform.
Third, if you just want to republish the content you wrote here, then I don't see a reason why you need a plugin to do that. You can just publish here, then republish on your blog. You own the content, after all. There's no need for a plugin to accomplish that. And true, a plugin will make it easier, but that will really just benefit the Wordpress site and not Musing.io. Well and good if you own a Wordpress site, but since not everyone on Musing.io has one, then the benefit will only affect a small percentage of the population, and it won't be an efficient use of the Musing.io team's time. Although personally, I would advise against republishing content like that. It's not good for SEO and you leave your Wordpress Site vulnerable to looking like a clone with no originality. So it's lose-lose, either way.
So, as far as I'm concerned a two-way Wordpress integration with Musing.io is a feature or plugin that should not be high on Musing.io's priority list. After all, the platform is still new and there are several improvements and features that could be done to improve the platform itself, without worrying about an integration that is non-essential, or worse detrimental, to the platform's functions. I'm not saying that this can't be revisited down the line, but at the moment, it shouldn't be a priority. Instead, Musing.io should be focused on two things: growing the user base and enriching the user experience. Integrations can come later.
I am a strong believer in Wordpress technology. From what i draw from the question here is the wordpress plugin which can be beneficial for musing.io too.
1. The plugin should be able to publish only the questions or answers or both, i publish on musing, to my wordpress blog.
2. It may not be as complicated to infringe the copyright laws but just to display my questions on my wordpress site, just as we integrate tweets on the site, it should integrate concepts build on musing to blog.
This will help musing to popularise. There are millions of blogs built on wordpress and they are read by billions of users. Having a plugin on wordpress will help those seeing the new content format to come on musing. I guess this is a fantastic idea and the creators of musing should consider it from long term perspective. Instead of spending on advertising one plugin could reduce significant marketting efforts