As well as having very similar titles, both Fire Emblem Warriors and the mobile spin-off Fire Emblem Heroes were in development at similar times. In an interview with Nintendo Everything, producer Yosuke Hayashi and director Hiroya Usuda talked about the relationship between the two games. According to Hayashi, the Warriors protagonists were inadvertently very similar to the duo from Heroes. This apparently meant that the Warriors’ Rowan and Lianna had to been redesigned. Check out the full interview here.
ND: Was the character design being done within the company?
Hayashi: Yes. Since both Awakening and Fates are in, there are a lot of characters designed by Kozaki Yusuke-san coming out. So as a basis, we intended to gather them to become pictures that don’t look too different from them. However, in Heroes, there are also protagonists of siblings based on gold.
Usuda: When we showed them to Nintendo and Intelligent Systems, proclaiming ‘These are our original characters for this time, Shion/Rowan and Lianna!’, they said ‘Actually we’re creating sibling characters like these…’ and showed the [then] unannounced characters. Then Heroes also had gold and white, and especially Sharon/Sharena and Lianna were way too similar to each other, including their background settings…
Hayashi: They told us ‘Hayashi-san, your team also did it with gold, huh!?’ (laughs). That’s why we revisited the designs, and we made some adjustments to them like changing their hair color.
Usuda: Although the changes were quite hectic, I personally am very glad that we could match up with the original team. Like, our minds think alike!

Just goes to show how most Fire Emblem designs are sadly generic, even the Lords.
generic maybe isnt the word, but they certainly arent the most creative. I yhink chrom and marths designs are nice, but when over half of your games have the cookie cutter blue haired caped lords maybe you need to try something g different
I appreciate corrin for this reason alone
Now imagine another universe where the character designs are being done by the lady who did Shadows of Valentia… A guy can only dream. Back to boring old Awakening/Fates guy until we all die.
He’s a man you know
https://kantopia.wordpress.com/2017/05/05/is-hidari-the-illustrator-a-man-or-a-woman-answer-hes-a-man/
Oops. That’s a screw up on my behalf.
https://youtu.be/HuX2CWeBHUw
Basically, I think it been in development for quite sometime during the release of Hyrule Warriors. I think they been focusing on redesigning the characters from Fire Emblem Awakeing from there generic designs.
Well I hope they only influenced character design. Heroes only captured my attention for a bit, I hope Warriors is much enticing.