I've been looking at my lunar returns to time things with my solar return. On the app astromatrix it says this month my moon is in the 7th house but on astroseek.com it says it's in the 6th house. I couldn't figure it out for awhile lol. So for lunar returns my moon will always be in the 6th house duh!
Only if you mean your natal houses and your natal moon is in the sixth. If you're talking about the lunar return houses, which one of those your moon is in will vary month to month.
Assuming both apps are talking about the same kind of house - either both of them mean the LR house or both of them mean the natal house - they may be using different house systems, or they may be counting a planet close to the cusp differently. If your moon is in the same sign as the descendant, it's in the seventh house whole sign, but if it's on the sixth house side of the cusp, all systems other than whole sign will put it in the sixth.
If your moon is on the sixth house side but very close to the descendant, some programs will call it a seventh house placement, even if they're not using whole sign. Others might call it sixth.
Without seeing the actual chart, it's also possible that you're looking at two different sets of houses: the lunar return houses on one app and the natal houses on the other. You might have your moon in the natal sixth house but lunar return seventh house, or vice versa.
I've wanted to know for a while with any chart in general, the significance of planets in the houses on the outer wheel, the "not natal" houses. For instance if I have no planets in the 7th house for my solar return chart but there are some in the outer wheels does that count? I also wanted to know are SR aspects to SR aspects as important as the ones aspecting natal planets? Because the app shows me those and on the web it shows me SR to natal aspects. Thank you for any feedback you can give me.
The houses in the outer wheel are the lunar return houses (if it's a lunar return chart) or the solar return houses (if it's a solar return chart). Your natal houses are where the houses fell at your moment of birth. The return houses are where the houses fall at the moment of the lunar or solar return.
The return houses are highly relevant in interpreting the return chart. So are the natal houses. If you have a planet that's in, say, your sixth natal house and your fourth return house, there's probably a fourth house theme going on with that planet, but it shows up in the sixth house component of a fourth house topic: perhaps there's a focus right now on taking care of home, duties to family, something like that. For a lunar return, it's usually a brief, fleeting focus - we're just looking at the underlying theme of the month - while for a solar return, it's more likely to be one of the things that's up for you this year.
SR to natal aspects are also highly relevant, and an essential part of interpreting the chart. You really can't interpret a return chart on its own. It only works in interaction with the natal.