Perhaps this is the time for Liverpool and Everton to work together and have a joint Merseyside women's stadium to give girls football a chance to really launch in this city.
We have shared a ground before, again out of necessity. Personally, I didn't have a problem with it. Felt a bit weird to say we both had the same stadium at the beginning, and it never quite stopped feeling weird when turning up to what was technically an 'away' game and my season ticket didn't grant me entry despite it doing so on 24 other weekends. But I think the arrangement played out perfectly fine.
Only the one stand was really used. This stand was, by design, split in half by the tunnel and the dressing rooms and the posh seats etc. There was no joint concourse. We took one side, Everton had the other. With the exception of the 'Home of..." signs on the front of the stadium, I'd have never really known Everton were also there. I don't see why that sense of split and invisible presence couldn't be replicated in a purpose built stadium. Though the neutral seat colours did help. I'm not sure Everton would feel quite so invisible if some of the seats were blue. And I don't think purple would make it feel like home, either.
As for fixture clashes: of the 17 league games played so far, ourselves and Everton have only been at home in the same game week twice - the first was on the same day, but kick offs were enough apart to have played two games back-to-back had they been at the same stadium (and when sharing Halton stadium, we did actually do a double-header of fixtures (we played first, everyone fucked off home right after
)), the second was on a Sat & Sun. So already it appears very possible for the WSL fixture list to not put us both at home in the same game week.
The bigger potential clash would be with the men's games, as you say. But the WSL (as of right now) has a very set way of deciding who plays when. Sunday is as 'norm' as it gets. The home team picks their kick off time. We like 2pm. Everton like 1pm. Fixtures moved for TV (under the current deals) go to midday Saturday (BBC), or Sunday in either the 4:30 or 18:45 slots (SKY). Since these slots are largely designed to not clash with the TV picks of the PL and since neither women's team uses the more traditional 3pm Sat k/o, there should be plenty of scope for not having anyone's men's and women's teams clashing. There are maybe only a handful of times a season when any kind of clash prevents me from separately watching both matches of ours teams regardless of who is home or away.
So all in all...
Would it be unthinkable from an us/them perspective? I'm saying no. And we've done it already so who cares now.
Would it be impractical in regard to the fixture list? I wouldn't think so, not for the majority of the season.
Is Walton Hall the best place? Honestly, I don't know. It's hard to tell if the minimal work Everton have done there is because the scope for expansion is so limited on this site or if it's because they haven't got a pot to piss in.
Which brings me onto what will likely be the biggest obstacle - expense and who foots the bill. Whatever 'shared stadium' might be settled on, it's hard to imagine Everton will financially contribute to its building.